diff --git a/src/main/java/com/axlabs/neo/grantshares/GrantSharesGov.java b/src/main/java/com/axlabs/neo/grantshares/GrantSharesGov.java
index ec5fb24..39a75b8 100644
--- a/src/main/java/com/axlabs/neo/grantshares/GrantSharesGov.java
+++ b/src/main/java/com/axlabs/neo/grantshares/GrantSharesGov.java
@@ -72,8 +72,6 @@ public class GrantSharesGov {
     static Event unpaused;
     @DisplayName("ProposalMigrated")
     static Event1Arg<Integer> migrated;
-    @DisplayName("Error")
-    static Event2Args<String, String> error;
     //endregion EVENTS
 
     /**
@@ -328,16 +326,16 @@ public static int createProposal(Hash160 proposer, Intent[] intents, String offc
      * @return The id of the proposal.
      */
     public static int createProposal(Hash160 proposer, Intent[] intents, String offchainUri, int linkedProposal,
-            int acceptanceRate, int quorum) {
+                                     int acceptanceRate, int quorum) {
 
-        if (!checkWitness(proposer)) fireErrorAndAbort("Not authorised", "createProposal");
+        if (!checkWitness(proposer)) Helper.abort("createProposal" + ": " +  "Not authorised");
         if (acceptanceRate < parameters.getInt(MIN_ACCEPTANCE_RATE_KEY) || acceptanceRate > 100)
-            fireErrorAndAbort("Invalid acceptance rate", "createProposal");
+            Helper.abort("createProposal" + ": " +  "Invalid acceptance rate");
         if (quorum < parameters.getInt(MIN_QUORUM_KEY) || quorum > 100)
-            fireErrorAndAbort("Invalid quorum", "createProposal");
+            Helper.abort("createProposal" + ": " +  "Invalid quorum");
         if (linkedProposal >= 0 && proposals.get(linkedProposal) == null)
-            fireErrorAndAbort("Linked proposal doesn't exist", "createProposal");
-        if (!areIntentsValid(intents)) fireErrorAndAbort("Invalid intents", "createProposal");
+            Helper.abort("createProposal" + ": " +  "Linked proposal doesn't exist");
+        if (!areIntentsValid(intents)) Helper.abort("createProposal" + ": " +  "Invalid intents");
 
         int id = Storage.getInt(getReadOnlyContext(), PROPOSALS_COUNT_KEY);
         int expiration = parameters.getInt(EXPIRATION_LENGTH_KEY) + getTime();
@@ -377,12 +375,12 @@ private static boolean areIntentsValid(Intent[] intents) {
     public static void endorseProposal(int id, Hash160 endorser) {
         abortIfPaused();
         if (members.get(endorser.toByteString()) == null || !checkWitness(endorser))
-            fireErrorAndAbort("Not authorised", "endorseProposal");
+            Helper.abort("endorseProposal" + ": " +  "Not authorised");
         ByteString proposalBytes = proposals.get(id);
-        if (proposalBytes == null) fireErrorAndAbort("Proposal doesn't exist", "endorseProposal");
+        if (proposalBytes == null) Helper.abort("endorseProposal" + ": " +  "Proposal doesn't exist");
         Proposal proposal = (Proposal) new StdLib().deserialize(proposalBytes);
-        if (proposal.expiration <= getTime()) fireErrorAndAbort("Proposal expired", "endorseProposal");
-        if (proposal.endorser != null) fireErrorAndAbort("Proposal already endorsed", "endorseProposal");
+        if (proposal.expiration <= getTime()) Helper.abort("endorseProposal" + ": " +  "Proposal expired");
+        if (proposal.endorser != null) Helper.abort("endorseProposal" + ": " +  "Proposal already endorsed");
 
         proposal.endorser = endorser;
         proposal.reviewEnd = getTime() + parameters.getInt(REVIEW_LENGTH_KEY);
@@ -404,17 +402,17 @@ public static void endorseProposal(int id, Hash160 endorser) {
      */
     public static void vote(int id, int vote, Hash160 voter) {
         abortIfPaused();
-        if (vote < -1 || vote > 1) fireErrorAndAbort("Invalid vote", "vote");
+        if (vote < -1 || vote > 1) Helper.abort("vote" + ": " +  "Invalid vote");
         if (members.get(voter.toByteString()) == null || !checkWitness(voter))
-            fireErrorAndAbort("Not authorised", "vote");
+            Helper.abort("vote" + ": " +  "Not authorised");
         ByteString proposalBytes = proposals.get(id);
-        if (proposalBytes == null) fireErrorAndAbort("Proposal doesn't exist", "vote");
+        if (proposalBytes == null) Helper.abort("vote" + ": " +  "Proposal doesn't exist");
         Proposal proposal = (Proposal) new StdLib().deserialize(proposalBytes);
         int time = getTime();
         if (proposal.endorser == null || time < proposal.reviewEnd || time >= proposal.votingEnd)
-            fireErrorAndAbort("Proposal not active", "vote");
+            Helper.abort("vote" + ": " +  "Proposal not active");
         ProposalVotes pv = (ProposalVotes) new StdLib().deserialize(proposalVotes.get(id));
-        if (pv.voters.containsKey(voter)) fireErrorAndAbort("Already voted on this proposal", "vote");
+        if (pv.voters.containsKey(voter)) Helper.abort("vote" + ": " +  "Already voted on this proposal");
 
         pv.voters.put(voter, vote);
         if (vote < 0) {
@@ -440,20 +438,20 @@ public static void vote(int id, int vote, Hash160 voter) {
     public static Object[] execute(int id) {
         abortIfPaused();
         ByteString proposalBytes = proposals.get(id);
-        if (proposalBytes == null) fireErrorAndAbort("Proposal doesn't exist", "execute");
+        if (proposalBytes == null) Helper.abort("execute" + ": " +  "Proposal doesn't exist");
         Proposal proposal = (Proposal) new StdLib().deserialize(proposalBytes);
         if (proposal.endorser == null || getTime() < proposal.timeLockEnd)
-            fireErrorAndAbort("Proposal not in execution phase", "execute");
-        if (proposal.executed) fireErrorAndAbort("Proposal already executed", "execute");
-        if (proposal.expiration <= getTime()) fireErrorAndAbort("Proposal expired", "execute");
+            Helper.abort("execute" + ": " +  "Proposal not in execution phase");
+        if (proposal.executed) Helper.abort("execute" + ": " +  "Proposal already executed");
+        if (proposal.expiration <= getTime()) Helper.abort("execute" + ": " +  "Proposal expired");
         ProposalData data = (ProposalData) new StdLib().deserialize(proposalData.get(id));
         ProposalVotes votes = (ProposalVotes) new StdLib().deserialize(proposalVotes.get(id));
         int voteCount = votes.approve + votes.abstain + votes.reject;
         if (voteCount * 100 / Storage.getInt(getReadOnlyContext(), MEMBERS_COUNT_KEY) < data.quorum)
-            fireErrorAndAbort("Quorum not reached", "execute");
+            Helper.abort("execute" + ": " +  "Quorum not reached");
         int yesNoCount = votes.approve + votes.reject;
         if (yesNoCount == 0 || (votes.approve * 100 / yesNoCount <= data.acceptanceRate))
-            fireErrorAndAbort("Proposal rejected", "execute");
+            Helper.abort("execute" + ": " +  "Proposal rejected");
 
         proposal.executed = true;
         Object[] returnVals = new Object[data.intents.length];
@@ -491,17 +489,17 @@ private static void abortOnInvalidValue(String paramKey, int value) {
             case VOTING_LENGTH_KEY:
             case TIMELOCK_LENGTH_KEY:
             case EXPIRATION_LENGTH_KEY:
-                if (value < 0) fireErrorAndAbort("Invalid parameter value", "changeParam");
+                if (value < 0) Helper.abort("changeParam" + ": " +  "Invalid parameter value");
                 break;
             case MIN_ACCEPTANCE_RATE_KEY:
             case MIN_QUORUM_KEY:
-                if (value < 0 || value > 100) fireErrorAndAbort("Invalid parameter value", "changeParam");
+                if (value < 0 || value > 100) Helper.abort("changeParam" + ": " +  "Invalid parameter value");
                 break;
             case MULTI_SIG_THRESHOLD_KEY:
-                if (value <= 0 || value > 100) fireErrorAndAbort("Invalid parameter value", "changeParam");
+                if (value <= 0 || value > 100) Helper.abort("changeParam" + ": " +  "Invalid parameter value");
                 break;
             default:
-                fireErrorAndAbort("Unknown parameter", "changeParam");
+                Helper.abort("changeParam" + ": " +  "Unknown parameter");
         }
     }
 
@@ -516,7 +514,7 @@ public static void addMember(ECPoint memberPubKey) {
         abortIfPaused();
         abortIfCallerIsNotSelf();
         Hash160 memberHash = createStandardAccount(memberPubKey);
-        if (members.get(memberHash.toByteString()) != null) fireErrorAndAbort("Already a member", "addMember");
+        if (members.get(memberHash.toByteString()) != null) Helper.abort("addMember" + ": " +  "Already a member");
         members.put(memberHash.toByteString(), memberPubKey.toByteString());
         Storage.put(ctx, MEMBERS_COUNT_KEY, Storage.getInt(getReadOnlyContext(), MEMBERS_COUNT_KEY) + 1);
         memberAdded.fire(memberHash);
@@ -533,7 +531,7 @@ public static void removeMember(ECPoint memberPubKey) {
         abortIfPaused();
         abortIfCallerIsNotSelf();
         Hash160 memberHash = createStandardAccount(memberPubKey);
-        if (members.get(memberHash.toByteString()) == null) fireErrorAndAbort("Not a member", "removeMember");
+        if (members.get(memberHash.toByteString()) == null) Helper.abort("removeMember" + ": " +  "Not a member");
         members.delete(memberHash.toByteString());
         Storage.put(ctx, MEMBERS_COUNT_KEY, Storage.getInt(getReadOnlyContext(), MEMBERS_COUNT_KEY) - 1);
         memberRemoved.fire(memberHash);
@@ -562,9 +560,9 @@ public static void pause() {
         try {
             membersMultiSigHash = calcMembersMultiSigAccount();
         } catch (Exception e) {
-            fireErrorAndAbort(e.getMessage(), "pause");
+            Helper.abort("pause" + ": " +  e.getMessage());
         }
-        if (!checkWitness(membersMultiSigHash)) fireErrorAndAbort("Not authorized", "pause");
+        if (!checkWitness(membersMultiSigHash)) Helper.abort("pause" + ": " +  "Not authorized");
         Storage.put(ctx, PAUSED_KEY, 1);
         paused.fire();
     }
@@ -574,27 +572,26 @@ public static void unpause() {
         try {
             membersMultiSigHash = calcMembersMultiSigAccount();
         } catch (Exception e) {
-            fireErrorAndAbort(e.getMessage(), "pause");
+            Helper.abort("pause" + ": " +  e.getMessage());
         }
-        if (!checkWitness(membersMultiSigHash)) fireErrorAndAbort("Not authorized", "unpause");
+        if (!checkWitness(membersMultiSigHash)) Helper.abort("unpause" + ": " +  "Not authorized");
         Storage.put(ctx, PAUSED_KEY, 0);
         unpaused.fire();
     }
 
     private static void abortIfCallerIsNotSelf() {
         if (Runtime.getCallingScriptHash() != Runtime.getExecutingScriptHash()) {
-            fireErrorAndAbort("Method only callable by the contract itself", "abortIfCallerIsNotSelf");
+            Helper.abort("abortIfCallerIsNotSelf" + ": " +  "Method only callable by the contract itself");
         }
     }
 
     public static void abortIfPaused() {
         if (Storage.getBoolean(getReadOnlyContext(), PAUSED_KEY)) {
-            fireErrorAndAbort("Contract is paused", "abortIfPaused");
+            Helper.abort("abortIfPaused" + ": " +  "Contract is paused");
         }
     }
 
-    private static void fireErrorAndAbort(String msg, String method) {
-        error.fire(msg, method);
-        Helper.abort();
+    private static void abortWithMessage(String method, String msg) {
+        Helper.abort(method + ": " + msg);
     }
 }
diff --git a/src/main/java/com/axlabs/neo/grantshares/GrantSharesTreasury.java b/src/main/java/com/axlabs/neo/grantshares/GrantSharesTreasury.java
index 4f54d66..d5bb325 100644
--- a/src/main/java/com/axlabs/neo/grantshares/GrantSharesTreasury.java
+++ b/src/main/java/com/axlabs/neo/grantshares/GrantSharesTreasury.java
@@ -61,6 +61,7 @@ public class GrantSharesTreasury {
     static final StorageMap funders = new StorageMap(ctx, FUNDERS_PREFIX); // [hash, List<ECPoint>]
     static final StorageMap whitelistedTokens = new StorageMap(ctx, WHITELISTED_TOKENS_PREFIX); // [hash, max_amount]
 
+    //region EVENTS
     @DisplayName("FunderAdded")
     static Event1Arg<Hash160> funderAdded;
     @DisplayName("FunderRemoved")
@@ -87,8 +88,7 @@ public class GrantSharesTreasury {
     static Event3Args<Hash160, Integer, Hash160> tokensReceived;
     @DisplayName("WhitelistedTokenMigrated")
     static Event2Args<Hash160, Integer> whitelistedTokenMigrated;
-    @DisplayName("Error")
-    static Event2Args<String, String> error;
+    //endregion EVENTS
 
     /**
      * Initialises this contract on deployment.
@@ -300,7 +300,7 @@ public static void setFundersMultiSigThresholdRatio(Integer value) {
         abortIfPaused();
         abortIfCallerIsNotOwner();
         if (value <= 0 || value > 100)
-            fireErrorAndAbort("Invalid threshold ratio", "setFundersMultiSigThresholdRatio");
+            Helper.abort("setFundersMultiSigThresholdRatio" + ": " + "Invalid threshold ratio");
         Storage.put(ctx, MULTI_SIG_THRESHOLD_KEY, value);
         thresholdChanged.fire(value);
     }
@@ -319,11 +319,11 @@ public static void setFundersMultiSigThresholdRatio(Integer value) {
     public static void addFunder(Hash160 accountHash, ECPoint[] publicKeys) {
         abortIfPaused();
         abortIfCallerIsNotOwner();
-        if (funders.get(accountHash.toByteString()) != null) fireErrorAndAbort("Already a funder", "addFunder");
-        if (!isValid(accountHash) || accountHash == zero()) fireErrorAndAbort("Invalid funder hash", "addFunder");
-        if (publicKeys.length == 0) fireErrorAndAbort("List of public keys is empty", "addFunder");
+        if (funders.get(accountHash.toByteString()) != null) Helper.abort("addFunder" + ": " + "Already a funder");
+        if (!isValid(accountHash) || accountHash == zero()) Helper.abort("addFunder" + ": " + "Invalid funder hash");
+        if (publicKeys.length == 0) Helper.abort("addFunder" + ": " + "List of public keys is empty");
         for (ECPoint key : publicKeys) {
-            if (!ECPoint.isValid(key)) fireErrorAndAbort("Invalid public key", "addFunder");
+            if (!ECPoint.isValid(key)) Helper.abort("addFunder" + ": " + "Invalid public key");
         }
         funders.put(accountHash.toByteString(), new StdLib().serialize(publicKeys));
         funderAdded.fire(accountHash);
@@ -339,7 +339,7 @@ public static void addFunder(Hash160 accountHash, ECPoint[] publicKeys) {
     public static void removeFunder(Hash160 accountHash) {
         abortIfPaused();
         abortIfCallerIsNotOwner();
-        if (funders.get(accountHash.toByteString()) == null) fireErrorAndAbort("Not a funder", "removeFunder");
+        if (funders.get(accountHash.toByteString()) == null) Helper.abort("removeFunder" + ": " + "Not a funder");
         funders.delete(accountHash.toByteString());
         funderRemoved.fire(accountHash);
     }
@@ -356,8 +356,8 @@ public static void removeFunder(Hash160 accountHash) {
     public static void addWhitelistedToken(Hash160 token, int maxFundingAmount) {
         abortIfPaused();
         abortIfCallerIsNotOwner();
-        if (!isValid(token) || token == zero()) fireErrorAndAbort("Invalid token hash", "addWhitelistedToken");
-        if (maxFundingAmount <= 0) fireErrorAndAbort("Invalid max funding amount", "addWhitelistedToken");
+        if (!isValid(token) || token == zero()) Helper.abort("addWhitelistedToken" + ": " + "Invalid token hash");
+        if (maxFundingAmount <= 0) Helper.abort("addWhitelistedToken" + ": " + "Invalid max funding amount");
         whitelistedTokens.put(token.toByteString(), maxFundingAmount);
         whitelistedTokenAdded.fire(token, maxFundingAmount);
     }
@@ -373,7 +373,7 @@ public static void removeWhitelistedToken(Hash160 token) {
         abortIfPaused();
         abortIfCallerIsNotOwner();
         if (whitelistedTokens.get(token.toByteString()) == null)
-            fireErrorAndAbort("Not a whitelisted token", "removeWhitelistedToken");
+            Helper.abort("removeWhitelistedToken" + ": " + "Not a whitelisted token");
         whitelistedTokens.delete(token.toByteString());
         whitelistedTokenRemoved.fire(token);
     }
@@ -392,8 +392,8 @@ public static void releaseTokens(Hash160 tokenContract, Hash160 to, int amount)
         abortIfPaused();
         abortIfCallerIsNotOwner();
         int maxFundingAmount = whitelistedTokens.getIntOrZero(tokenContract.toByteString());
-        if (maxFundingAmount == 0) fireErrorAndAbort("Token not whitelisted", "releaseTokens");
-        if (amount > maxFundingAmount) fireErrorAndAbort("Above token's max funding amount", "releaseTokens");
+        if (maxFundingAmount == 0) Helper.abort("releaseTokens" + ": " + "Token not whitelisted");
+        if (amount > maxFundingAmount) Helper.abort("releaseTokens" + ": " + "Above token's max funding amount");
         Object[] params = new Object[]{Runtime.getExecutingScriptHash(), to, amount, new Object[]{}};
         boolean success = (boolean) Contract.call(tokenContract, "transfer", CallFlags.All, params);
         if (success) {
@@ -410,14 +410,14 @@ public static void releaseTokens(Hash160 tokenContract, Hash160 to, int amount)
      * paused.
      */
     public static void drain() {
-        if (!isPaused()) fireErrorAndAbort("Contract is not paused", "drain");
+        if (!isPaused()) Helper.abort("drain" + ": " + "Contract is not paused");
         Hash160 fundersMultiAddress = null;
         try {
             fundersMultiAddress = calcFundersMultiSigAddress();
         } catch (Exception e) {
-            fireErrorAndAbort(e.getMessage(), "drain");
+            Helper.abort("drain" + ": " + e.getMessage());
         }
-        if (!checkWitness(fundersMultiAddress)) fireErrorAndAbort("Not authorized", "drain");
+        if (!checkWitness(fundersMultiAddress)) Helper.abort("drain" + ": " + "Not authorized");
         Hash160 selfHash = Runtime.getExecutingScriptHash();
         Iterator<ByteString> it = whitelistedTokens.find((byte) (RemovePrefix | KeysOnly));
         while (it.next()) {
@@ -442,7 +442,7 @@ public static void voteCommitteeMemberWithLeastVotes() {
         abortIfPaused();
         ECPoint c = getCommitteeMemberWithLeastVotes();
         if (!new NeoToken().vote(Runtime.getExecutingScriptHash(), c))
-            fireErrorAndAbort("Failed voting on candidate", "voteCommitteeMemberWithLeastVotes");
+            Helper.abort("voteCommitteeMemberWithLeastVotes" + ": " + "Failed voting on candidate");
         voted.fire(c);
     }
 
@@ -481,15 +481,14 @@ public static void updateContract(ByteString nef, String manifest, Object data)
 
     private static void abortIfCallerIsNotOwner() {
         if (Runtime.getCallingScriptHash().toByteString() != Storage.get(getReadOnlyContext(), OWNER_KEY))
-            fireErrorAndAbort("Not authorised", "abortIfCallerIsNotOwner");
+            Helper.abort("abortIfCallerIsNotOwner" + ": " + "Not authorised");
     }
 
     private static void abortIfPaused() {
-        if (isPaused()) fireErrorAndAbort("Contract is paused", "abortIfCallerIsNotOwner");
+        if (isPaused()) Helper.abort("abortIfCallerIsNotOwner" + ": " + "Contract is paused");
     }
 
-    private static void fireErrorAndAbort(String msg, String method) {
-        error.fire(msg, method);
-        Helper.abort();
+    private static void abortWithMessage(String method, String msg) {
+        Helper.abort(method + ": " + msg);
     }
 }
diff --git a/src/test/java/com/axlabs/neo/grantshares/GovernanceMembersTest.java b/src/test/java/com/axlabs/neo/grantshares/GovernanceMembersTest.java
index f50c3fc..59d0291 100644
--- a/src/test/java/com/axlabs/neo/grantshares/GovernanceMembersTest.java
+++ b/src/test/java/com/axlabs/neo/grantshares/GovernanceMembersTest.java
@@ -10,6 +10,7 @@
 import io.neow3j.test.DeployConfig;
 import io.neow3j.test.DeployConfiguration;
 import io.neow3j.transaction.AccountSigner;
+import io.neow3j.transaction.exceptions.TransactionConfigurationException;
 import io.neow3j.types.CallFlags;
 import io.neow3j.types.ContractParameter;
 import io.neow3j.types.Hash256;
@@ -26,32 +27,14 @@
 import java.util.List;
 import java.util.stream.Collectors;
 
-import static com.axlabs.neo.grantshares.util.TestHelper.ADD_MEMBER;
-import static com.axlabs.neo.grantshares.util.TestHelper.ALICE;
-import static com.axlabs.neo.grantshares.util.TestHelper.BOB;
-import static com.axlabs.neo.grantshares.util.TestHelper.CALC_MEMBER_MULTI_SIG_ACC;
-import static com.axlabs.neo.grantshares.util.TestHelper.CHARLIE;
-import static com.axlabs.neo.grantshares.util.TestHelper.DENISE;
-import static com.axlabs.neo.grantshares.util.TestHelper.GET_MEMBERS;
-import static com.axlabs.neo.grantshares.util.TestHelper.MEMBER_ADDED;
-import static com.axlabs.neo.grantshares.util.TestHelper.MEMBER_REMOVED;
-import static com.axlabs.neo.grantshares.util.TestHelper.PHASE_LENGTH;
-import static com.axlabs.neo.grantshares.util.TestHelper.PROPOSAL_EXECUTED;
-import static com.axlabs.neo.grantshares.util.TestHelper.REMOVE_MEMBER;
-import static com.axlabs.neo.grantshares.util.TestHelper.assertAborted;
-import static com.axlabs.neo.grantshares.util.TestHelper.createAndEndorseProposal;
-import static com.axlabs.neo.grantshares.util.TestHelper.createMultiSigAccount;
-import static com.axlabs.neo.grantshares.util.TestHelper.prepareDeployParameter;
-import static com.axlabs.neo.grantshares.util.TestHelper.voteForProposal;
+import static com.axlabs.neo.grantshares.util.TestHelper.*;
 import static io.neow3j.types.ContractParameter.array;
-import static io.neow3j.types.ContractParameter.hash160;
-import static io.neow3j.types.ContractParameter.publicKey;
+import static io.neow3j.types.ContractParameter.*;
 import static org.hamcrest.MatcherAssert.assertThat;
-import static org.hamcrest.Matchers.contains;
-import static org.hamcrest.Matchers.containsInAnyOrder;
-import static org.hamcrest.Matchers.containsString;
-import static org.hamcrest.Matchers.nullValue;
+import static org.hamcrest.Matchers.*;
 import static org.hamcrest.core.Is.is;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 @ContractTest(contracts = GrantSharesGov.class, blockTime = 1, configFile = "default.neo-express",
         batchFile = "setup.batch")
@@ -79,7 +62,6 @@ public static DeployConfiguration deployConfig() throws Exception {
     @BeforeAll
     public static void setUp() throws Throwable {
         neow3j = ext.getNeow3j();
-        neow3j.allowTransmissionOnFault();
         gov = new GrantSharesGovContract(ext.getDeployedContract(GrantSharesGov.class).getScriptHash(), neow3j);
         alice = ext.getAccount(ALICE);
         bob = ext.getAccount(BOB);
@@ -90,9 +72,8 @@ public static void setUp() throws Throwable {
     //region ADD MEMBER
     @Test
     public void fail_calling_add_member_directly() throws Throwable {
-        Hash256 tx = gov.invokeFunction(ADD_MEMBER, hash160(bob)).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Method only callable by the contract itself", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(ADD_MEMBER, hash160(bob)).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Method only callable by the contract itself"));
     }
 
     @Order(1) // Is executed before the execute_remove_member test which removes bob from members.
@@ -118,8 +99,7 @@ public void execute_add_member() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign().send()
-                .getSendRawTransaction().getHash();
+        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign().send().getSendRawTransaction().getHash();
         Await.waitUntilTransactionIsExecuted(tx, neow3j);
 
         NeoApplicationLog.Execution execution = neow3j.getApplicationLog(tx).send()
@@ -160,9 +140,8 @@ public void fail_execute_add_member_with_already_member() throws Throwable {
         voteForProposal(gov, neow3j, id, charlie);
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Already a member", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Already a member"));
     }
 
     @Test
@@ -193,9 +172,8 @@ public void fail_execute_add_member_with_invalid_public_key() throws Throwable {
     //region REMOVE MEMBER
     @Test
     public void fail_calling_remove_member_directly() throws Throwable {
-        Hash256 tx = gov.invokeFunction(REMOVE_MEMBER, hash160(bob)).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Method only callable by the contract itself", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(REMOVE_MEMBER, hash160(bob)).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Method only callable by the contract itself"));
     }
 
     @Order(2) // Is executed right after the execute_add_member test to remove bob from members
@@ -220,8 +198,7 @@ public void execute_remove_member() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign().send()
-                .getSendRawTransaction().getHash();
+        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign().send().getSendRawTransaction().getHash();
         Await.waitUntilTransactionIsExecuted(tx, neow3j);
 
         NeoApplicationLog.Execution execution = neow3j.getApplicationLog(tx).send()
@@ -260,9 +237,8 @@ public void fail_execute_remove_member_with_non_member() throws Throwable {
         voteForProposal(gov, neow3j, id, charlie);
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(charlie))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not a member", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Not a member"));
     }
 
     //endregion REMOVE MEMBER
diff --git a/src/test/java/com/axlabs/neo/grantshares/GovernanceParametersTest.java b/src/test/java/com/axlabs/neo/grantshares/GovernanceParametersTest.java
index a253aa4..9d9288f 100644
--- a/src/test/java/com/axlabs/neo/grantshares/GovernanceParametersTest.java
+++ b/src/test/java/com/axlabs/neo/grantshares/GovernanceParametersTest.java
@@ -10,6 +10,7 @@
 import io.neow3j.test.DeployConfig;
 import io.neow3j.test.DeployConfiguration;
 import io.neow3j.transaction.AccountSigner;
+import io.neow3j.transaction.exceptions.TransactionConfigurationException;
 import io.neow3j.types.ContractParameter;
 import io.neow3j.types.Hash256;
 import io.neow3j.utils.Await;
@@ -40,7 +41,6 @@
 import static com.axlabs.neo.grantshares.util.TestHelper.REVIEW_LENGTH_KEY;
 import static com.axlabs.neo.grantshares.util.TestHelper.TIMELOCK_LENGTH_KEY;
 import static com.axlabs.neo.grantshares.util.TestHelper.VOTING_LENGTH_KEY;
-import static com.axlabs.neo.grantshares.util.TestHelper.assertAborted;
 import static com.axlabs.neo.grantshares.util.TestHelper.createAndEndorseProposal;
 import static com.axlabs.neo.grantshares.util.TestHelper.prepareDeployParameter;
 import static com.axlabs.neo.grantshares.util.TestHelper.voteForProposal;
@@ -50,6 +50,8 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.nullValue;
 import static org.hamcrest.core.Is.is;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 @ContractTest(contracts = GrantSharesGov.class, blockTime = 1, configFile = "default.neo-express",
         batchFile = "setup.batch")
@@ -75,7 +77,6 @@ public static DeployConfiguration deployConfig() throws Exception {
     @BeforeAll
     public static void setUp() throws Throwable {
         neow3j = ext.getNeow3j();
-        neow3j.allowTransmissionOnFault();
         gov = new GrantSharesGovContract(ext.getDeployedContract(GrantSharesGov.class).getScriptHash(), neow3j);
         alice = ext.getAccount(ALICE);
         bob = ext.getAccount(BOB);
@@ -138,9 +139,8 @@ public void execute_change_parameter() throws Throwable {
 
     @Test
     public void fail_calling_change_parameter_directly() throws Throwable {
-        Hash256 tx = gov.invokeFunction(CHANGE_PARAM, string(REVIEW_LENGTH_KEY), integer(100))
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Method only callable by the contract itself", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(CHANGE_PARAM, string(REVIEW_LENGTH_KEY), integer(100)).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Method only callable by the contract itself"));
     }
 
     @Test
@@ -158,9 +158,8 @@ public void fail_changing_unknown_parameter() throws Throwable {
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Unknown parameter", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Unknown parameter"));
     }
 
     @Test
@@ -176,9 +175,8 @@ public void fail_changing_voting_length_to_negative_value() throws Throwable {
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid parameter value", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid parameter value"));
         assertThat(gov.getParameter(VOTING_LENGTH_KEY).getInteger().intValue(), is(PHASE_LENGTH * 1000));
     }
 
@@ -195,9 +193,8 @@ public void fail_changing_min_acceptance_rate_to_negative_value() throws Throwab
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid parameter value", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid parameter value"));
         assertThat(gov.getParameter(MIN_ACCEPTANCE_RATE_KEY).getInteger().intValue(), is(MIN_ACCEPTANCE_RATE));
     }
 
@@ -214,9 +211,8 @@ public void fail_changing_min_acceptance_rate_to_more_than_hundred() throws Thro
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid parameter value", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid parameter value"));
         assertThat(gov.getParameter(MIN_ACCEPTANCE_RATE_KEY).getInteger().intValue(), is(MIN_ACCEPTANCE_RATE));
     }
 
@@ -233,9 +229,8 @@ public void fail_changing_multisig_threshold_to_zero() throws Throwable {
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid parameter value", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid parameter value"));
         assertThat(gov.getParameter(MULTI_SIG_THRESHOLD_KEY).getInteger().intValue(), is(MULTI_SIG_THRESHOLD_RATIO));
     }
 
@@ -252,9 +247,8 @@ public void fail_changing_multisig_threshold_to_more_than_hundred() throws Throw
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid parameter value", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid parameter value"));
         assertThat(gov.getParameter(MULTI_SIG_THRESHOLD_KEY).getInteger().intValue(), is(MULTI_SIG_THRESHOLD_RATIO));
     }
 
diff --git a/src/test/java/com/axlabs/neo/grantshares/GrantSharesGovTest.java b/src/test/java/com/axlabs/neo/grantshares/GrantSharesGovTest.java
index 9970179..fd5793f 100644
--- a/src/test/java/com/axlabs/neo/grantshares/GrantSharesGovTest.java
+++ b/src/test/java/com/axlabs/neo/grantshares/GrantSharesGovTest.java
@@ -18,6 +18,7 @@
 import io.neow3j.transaction.AccountSigner;
 import io.neow3j.transaction.Transaction;
 import io.neow3j.transaction.Witness;
+import io.neow3j.transaction.exceptions.TransactionConfigurationException;
 import io.neow3j.types.CallFlags;
 import io.neow3j.types.ContractParameter;
 import io.neow3j.types.Hash160;
@@ -36,6 +37,7 @@
 import java.math.BigInteger;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.Collections;
 import java.util.List;
 
 import static com.axlabs.neo.grantshares.util.TestHelper.ADD_MEMBER;
@@ -61,7 +63,6 @@
 import static com.axlabs.neo.grantshares.util.TestHelper.UPDATE_CONTRACT;
 import static com.axlabs.neo.grantshares.util.TestHelper.VOTE;
 import static com.axlabs.neo.grantshares.util.TestHelper.VOTED;
-import static com.axlabs.neo.grantshares.util.TestHelper.assertAborted;
 import static com.axlabs.neo.grantshares.util.TestHelper.createAndEndorseProposal;
 import static com.axlabs.neo.grantshares.util.TestHelper.createMultiSigAccount;
 import static com.axlabs.neo.grantshares.util.TestHelper.createSimpleProposal;
@@ -82,8 +83,7 @@
 import static org.hamcrest.Matchers.nullValue;
 import static org.hamcrest.core.Is.is;
 import static org.hamcrest.core.IsNot.not;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 
 @ContractTest(contracts = GrantSharesGov.class, blockTime = 1, configFile = "default.neo-express",
         batchFile = "setup.batch")
@@ -91,8 +91,10 @@
 public class GrantSharesGovTest {
 
     @RegisterExtension
-    private static ContractTestExtension ext = new ContractTestExtension();
-
+    private static final ContractTestExtension ext = new ContractTestExtension();
+    private final static Path TESTCONTRACT_NEF_FILE = Paths.get("TestContract.nef");
+    private final static Path TESTCONTRACT_MANIFEST_FILE =
+            Paths.get("TestGrantSharesGov.manifest.json");
     private static Neow3j neow3j;
     private static GrantSharesGovContract gov;
     private static Account alice; // Set to be a DAO member.
@@ -100,10 +102,6 @@ public class GrantSharesGovTest {
     private static Account charlie; // Set to be a DAO member.
     private static int defaultProposalId;
 
-    private final static Path TESTCONTRACT_NEF_FILE = Paths.get("TestContract.nef");
-    private final static Path TESTCONTRACT_MANIFEST_FILE =
-            Paths.get("TestGrantSharesGov.manifest.json");
-
     @DeployConfig(GrantSharesGov.class)
     public static DeployConfiguration deployConfig() throws Exception {
         DeployConfiguration config = new DeployConfiguration();
@@ -115,7 +113,6 @@ public static DeployConfiguration deployConfig() throws Exception {
     @BeforeAll
     public static void setUp() throws Throwable {
         neow3j = ext.getNeow3j();
-        neow3j.allowTransmissionOnFault();
         gov = new GrantSharesGovContract(ext.getDeployedContract(GrantSharesGov.class).getScriptHash(), neow3j);
         alice = ext.getAccount(ALICE);
         bob = ext.getAccount(BOB);
@@ -158,7 +155,7 @@ public void succeed_creating_and_retrieving_proposal() throws Throwable {
                 .getApplicationLog().getExecutions().get(0).getStack().get(0).getInteger().intValue();
 
         // 2. Test correct setup of the created proposal.
-        NeoInvokeFunction r = gov.callInvokeFunction(GET_PROPOSAL, asList(integer(id)));
+        NeoInvokeFunction r = gov.callInvokeFunction(GET_PROPOSAL, Collections.singletonList(integer(id)));
         ProposalStruct p = new ProposalStruct(r.getInvocationResult().getStack().get(0).getList());
         assertThat(p.id, is(id));
         assertThat(p.proposer, is(alice.getScriptHash()));
@@ -196,9 +193,8 @@ public void fail_creating_with_missing_linked_proposal() throws Throwable {
                 array(gov.getScriptHash(), alice.getScriptHash(), 1));
         String offchainUri = "fail_creating_with_missing_linked_proposal";
 
-        Hash256 tx = gov.createProposal(alice.getScriptHash(), offchainUri, 1000, intent)
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Linked proposal doesn't exist", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.createProposal(alice.getScriptHash(), offchainUri, 1000, intent).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Linked proposal doesn't exist"));
     }
 
     @Test
@@ -208,13 +204,11 @@ public void fail_creating_with_bad_quorum() throws Throwable {
                 array(gov.getScriptHash(), alice.getScriptHash(), 1));
         String offchainUri = "fail_creating_with_bad_quorum";
 
-        Hash256 tx = gov.createProposal(alice.getScriptHash(), offchainUri, -1, MIN_ACCEPTANCE_RATE, MIN_QUORUM - 1,
-                intent).signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid quorum", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.createProposal(alice.getScriptHash(), offchainUri, -1, MIN_ACCEPTANCE_RATE, MIN_QUORUM - 1, intent).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid quorum"));
 
-        tx = gov.createProposal(alice.getScriptHash(), offchainUri, -1, MIN_ACCEPTANCE_RATE, 101, intent)
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid quorum", neow3j);
+        e = assertThrows(TransactionConfigurationException.class, () -> gov.createProposal(alice.getScriptHash(), offchainUri, -1, MIN_ACCEPTANCE_RATE, 101, intent).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid quorum"));
     }
 
     @Test
@@ -224,13 +218,11 @@ public void fail_creating_with_bad_acceptance_rate() throws Throwable {
                 array(gov.getScriptHash(), alice.getScriptHash(), 1));
         String offchainUri = "fail_creating_with_bad_acceptance_rate";
 
-        Hash256 tx = gov.createProposal(alice.getScriptHash(), offchainUri, -1, MIN_ACCEPTANCE_RATE - 1, MIN_QUORUM,
-                intent).signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid acceptance rate", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.createProposal(alice.getScriptHash(), offchainUri, -1, MIN_ACCEPTANCE_RATE - 1, MIN_QUORUM, intent).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid acceptance rate"));
 
-        tx = gov.createProposal(alice.getScriptHash(), offchainUri, -1, 101, MIN_QUORUM, intent)
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid acceptance rate", neow3j);
+        e = assertThrows(TransactionConfigurationException.class, () -> gov.createProposal(alice.getScriptHash(), offchainUri, -1, 101, MIN_QUORUM, intent).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid acceptance rate"));
     }
 
     @Test
@@ -286,17 +278,15 @@ public void succeed_endorsing_with_member() throws Throwable {
     @Test
     @Order(0)
     public void fail_endorsing_with_non_member() throws Throwable {
-        Hash256 tx = gov.endorseProposal(defaultProposalId, bob.getScriptHash())
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.endorseProposal(defaultProposalId, bob.getScriptHash()).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
     @Order(0)
     public void fail_endorsing_with_member_but_wrong_signer() throws Throwable {
-        Hash256 tx = gov.endorseProposal(defaultProposalId, alice.getScriptHash())
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.endorseProposal(defaultProposalId, alice.getScriptHash()).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
@@ -314,17 +304,15 @@ public void fail_endorsing_already_endorsed_proposal() throws Throwable {
         Await.waitUntilTransactionIsExecuted(endorseTx, neow3j);
 
         // 3. Endorse again
-        Hash256 tx = gov.endorseProposal(id, alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal already endorsed", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.endorseProposal(id, alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal already endorsed"));
     }
 
     @Test
     @Order(0)
     public void fail_endorsing_non_existent_proposal() throws Throwable {
-        Hash256 tx = gov.endorseProposal(1000, alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal doesn't exist", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.endorseProposal(1000, alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal doesn't exist"));
     }
 
     @Test
@@ -336,9 +324,8 @@ public void fail_endorsing_expired_proposal() throws Throwable {
                 .getApplicationLog().getExecutions().get(0).getStack().get(0).getInteger().intValue();
         ext.fastForwardOneBlock(PHASE_LENGTH);
 
-        Hash256 tx = gov.endorseProposal(id, alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal expired", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.endorseProposal(id, alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal expired"));
     }
 
     @Test
@@ -401,17 +388,15 @@ public void fail_voting_in_review_and_queued_phase() throws Throwable {
         Await.waitUntilTransactionIsExecuted(endorseTx, neow3j);
 
         // 3. Vote in review phase
-        Hash256 tx = gov.vote(id, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal not active", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(id, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal not active"));
 
         // 5. Fast-forward till after the voting phase.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
         // 4. Vote in queued or later phase
-        tx = gov.vote(id, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal not active", neow3j);
+        e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(id, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal not active"));
     }
 
     @Test
@@ -440,9 +425,8 @@ public void fail_voting_multiple_times() throws Throwable {
         Await.waitUntilTransactionIsExecuted(voteTx, neow3j);
 
         // 5. Vote the second time
-        Hash256 tx = gov.vote(id, 1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Already voted on this proposal", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(id, 1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Already voted on this proposal"));
 
         // 6. Check votes
         ProposalStruct proposal = gov.getProposal(id);
@@ -457,35 +441,31 @@ public void fail_voting_multiple_times() throws Throwable {
     @Order(0)
     public void fail_voting_with_non_member() throws Throwable {
         // Vote on the default proposal. Doesn't matter in what phase it is.
-        Hash256 tx = gov.vote(defaultProposalId, -1, bob.getScriptHash()).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(defaultProposalId, -1, bob.getScriptHash()).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
     @Order(0)
     public void fail_voting_on_non_existent_proposal() throws Throwable {
-        Hash256 tx = gov.vote(1000, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign()
-                .send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal doesn't exist", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(1000, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal doesn't exist"));
     }
 
     @Test
     @Order(0)
     public void fail_voting_on_not_endorsed_proposal() throws Throwable {
         // Vote on the default proposal. Doesn't matter in what phase it is.
-        Hash256 tx = gov.vote(defaultProposalId, -1, charlie.getScriptHash())
-                .signers(AccountSigner.calledByEntry(charlie)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal not active", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(defaultProposalId, -1, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal not active"));
     }
 
     @Test
     @Order(0)
     public void fail_voting_with_invalid_vote() throws Throwable {
         // Vote on the default proposal. Doesn't matter in what phase it is.
-        Hash256 tx = gov.vote(defaultProposalId, 2, charlie.getScriptHash())
-                .signers(AccountSigner.calledByEntry(charlie)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid vote", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(defaultProposalId, 2, charlie.getScriptHash()).signers(AccountSigner.calledByEntry(charlie)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid vote"));
     }
 
     @Test
@@ -558,7 +538,7 @@ public void create_proposal_with_large_intents_and_offchainUri() throws Throwabl
         int id = neow3j.getApplicationLog(tx).send().getApplicationLog().getExecutions().get(0)
                 .getStack().get(0).getInteger().intValue();
 
-        NeoInvokeFunction r = gov.callInvokeFunction(GET_PROPOSAL, asList(integer(id)));
+        NeoInvokeFunction r = gov.callInvokeFunction(GET_PROPOSAL, Collections.singletonList(integer(id)));
         ProposalStruct p = new ProposalStruct(r.getInvocationResult().getStack().get(0).getList());
         assertThat(p.id, is(id));
         assertThat(p.proposer, is(bob.getScriptHash()));
@@ -621,17 +601,15 @@ public void get_number_of_proposals() throws IOException {
     @Test
     @Order(0)
     public void fail_pausing_contract_without_members_account() throws Throwable {
-        Hash256 tx = gov.invokeFunction(PAUSE).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorized", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(PAUSE).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorized"));
     }
 
     @Test
     @Order(0)
     public void fail_unpausing_contract_without_members_account() throws Throwable {
-        Hash256 tx = gov.invokeFunction(UNPAUSE).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorized", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(UNPAUSE).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorized"));
     }
 
     // Is executed as the first test of series of test that require the contract to be paused.
@@ -667,9 +645,8 @@ public void fail_execute_update_contract_directly() throws Throwable {
         ContractManifest manifest = getObjectMapper()
                 .readValue(manifestFile, ContractManifest.class);
         String manifestString = getObjectMapper().writeValueAsString(manifest);
-        Hash256 tx = gov.updateContract(nef.toArray(), manifestString, null).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Method only callable by the contract itself", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.updateContract(nef.toArray(), manifestString, null).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Method only callable by the contract itself"));
     }
 
     @Test
@@ -678,66 +655,57 @@ public void fail_create_proposal_calling_contract_management() throws Throwable
         IntentParam intent1 = IntentParam.addMemberProposal(gov.getScriptHash(), alice.getECKeyPair().getPublicKey());
         IntentParam intent2 = new IntentParam(ContractManagement.SCRIPT_HASH, "destroy");
 
-        Hash256 tx = gov.createProposal(alice.getScriptHash(), "fail_create_proposal_calling_contract_management", -1,
-                        intent1, intent2).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid intents", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.createProposal(alice.getScriptHash(), "fail_create_proposal_calling_contract_management", -1, intent1, intent2).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid intents"));
     }
 
     @Order(11)
     @Test
     public void fail_change_param_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.invokeFunction(CHANGE_PARAM, string(MIN_ACCEPTANCE_RATE_KEY), integer(50))
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(CHANGE_PARAM, string(MIN_ACCEPTANCE_RATE_KEY), integer(50)).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(12)
     @Test
     public void fail_add_member_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.invokeFunction(ADD_MEMBER, publicKey(bob.getECKeyPair().getPublicKey().getEncoded(true)))
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(ADD_MEMBER, publicKey(bob.getECKeyPair().getPublicKey().getEncoded(true))).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(13)
     @Test
     public void fail_remove_member_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.invokeFunction(REMOVE_MEMBER, publicKey(bob.getECKeyPair().getPublicKey().getEncoded(true)))
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.invokeFunction(REMOVE_MEMBER, publicKey(bob.getECKeyPair().getPublicKey().getEncoded(true))).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(14)
     @Test
     public void fail_execute_proposal_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.execute(defaultProposalId).signers(AccountSigner.calledByEntry(bob)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(defaultProposalId).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(15)
     @Test
     public void fail_vote_on_proposal_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.vote(defaultProposalId, 1, alice.getScriptHash()).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.vote(defaultProposalId, 1, alice.getScriptHash()).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(16)
     @Test
     public void fail_endorse_proposal_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.endorseProposal(defaultProposalId, alice.getScriptHash())
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.endorseProposal(defaultProposalId, alice.getScriptHash()).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(17)
     @Test
     public void fail_update_contract_on_paused_contract() throws Throwable {
-        Hash256 tx = gov.updateContract(new byte[]{0x01, 0x02, 0x03}, "the manifest", null)
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.updateContract(new byte[]{0x01, 0x02, 0x03}, "the manifest", null).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     // Must be executed after all tests orderd after the test that pauses the contract.
diff --git a/src/test/java/com/axlabs/neo/grantshares/GrantSharesTreasuryTest.java b/src/test/java/com/axlabs/neo/grantshares/GrantSharesTreasuryTest.java
index d9cf9ae..ebdbda8 100644
--- a/src/test/java/com/axlabs/neo/grantshares/GrantSharesTreasuryTest.java
+++ b/src/test/java/com/axlabs/neo/grantshares/GrantSharesTreasuryTest.java
@@ -21,6 +21,7 @@
 import io.neow3j.transaction.AccountSigner;
 import io.neow3j.transaction.Transaction;
 import io.neow3j.transaction.Witness;
+import io.neow3j.transaction.exceptions.TransactionConfigurationException;
 import io.neow3j.types.CallFlags;
 import io.neow3j.types.ContractParameter;
 import io.neow3j.types.Hash160;
@@ -40,6 +41,7 @@
 import java.math.BigInteger;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -55,7 +57,6 @@
 import static com.axlabs.neo.grantshares.util.TestHelper.PHASE_LENGTH;
 import static com.axlabs.neo.grantshares.util.TestHelper.UNPAUSE;
 import static com.axlabs.neo.grantshares.util.TestHelper.UPDATE_CONTRACT;
-import static com.axlabs.neo.grantshares.util.TestHelper.assertAborted;
 import static com.axlabs.neo.grantshares.util.TestHelper.createAndEndorseProposal;
 import static com.axlabs.neo.grantshares.util.TestHelper.createMultiSigAccount;
 import static com.axlabs.neo.grantshares.util.TestHelper.prepareDeployParameter;
@@ -73,8 +74,7 @@
 import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.core.Is.is;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 
 @ContractTest(contracts = {GrantSharesGov.class, GrantSharesTreasury.class},
         blockTime = 1, configFile = "default.neo-express", batchFile = "setup.batch")
@@ -134,7 +134,6 @@ public static DeployConfiguration deployConfigTreasury(DeployContext ctx) throws
     @BeforeAll
     public static void setUp() throws Throwable {
         neow3j = ext.getNeow3j();
-        neow3j.allowTransmissionOnFault();
 
         // contracts
         gov = new GrantSharesGovContract(
@@ -206,33 +205,29 @@ public void succeed_voting_on_committee_member() throws Throwable {
     @Test
     @Order(0)
     public void fail_calling_add_whitelisted_token_directly() throws Throwable {
-        Hash256 tx = treasury.addWhitelistedToken(GasToken.SCRIPT_HASH, 1).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.addWhitelistedToken(GasToken.SCRIPT_HASH, 1).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
     @Order(0)
     public void fail_calling_remove_whitelisted_token_directly() throws Throwable {
-        Hash256 tx = treasury.removeWhitelistedToken(GasToken.SCRIPT_HASH).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.removeWhitelistedToken(GasToken.SCRIPT_HASH).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
     @Order(0)
     public void fail_calling_add_funder_directly() throws Throwable {
-        Hash256 tx = treasury.addFunder(alice.getScriptHash(), alice.getECKeyPair().getPublicKey())
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.addFunder(alice.getScriptHash(), alice.getECKeyPair().getPublicKey()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
     @Order(0)
     public void fail_calling_remove_funder_directly() throws Throwable {
-        Hash256 tx = treasury.removeFunder(charlie.getScriptHash()).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.removeFunder(charlie.getScriptHash()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
@@ -259,9 +254,8 @@ public void fail_execute_update_contract_directly() throws Throwable {
 
         ContractParameter data = string("update contract");
 
-        Hash256 tx = treasury.invokeFunction(UPDATE_CONTRACT, byteArray(nef.toArray()), byteArray(manifestBytes), data)
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.invokeFunction(UPDATE_CONTRACT, byteArray(nef.toArray()), byteArray(manifestBytes), data).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
@@ -281,9 +275,8 @@ public void fail_release_tokens_with_non_whitelisted_token() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Token not whitelisted", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Token not whitelisted"));
     }
 
     @Test
@@ -303,24 +296,22 @@ public void fail_release_tokens_with_to_high_amount() throws Throwable {
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Above token's max funding amount", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Above token's max funding amount"));
     }
 
     @Test
     @Order(0)
     public void fail_calling_release_tokens_directly() throws Throwable {
-        Hash256 tx = treasury.releaseTokens(GasToken.SCRIPT_HASH, alice.getScriptHash(), BigInteger.ONE)
-                .signers(AccountSigner.calledByEntry(bob)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorised", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.releaseTokens(GasToken.SCRIPT_HASH, alice.getScriptHash(), BigInteger.ONE).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorised"));
     }
 
     @Test
     @Order(0)
     public void fail_adding_invalid_funder() throws Throwable {
         ContractParameter intent = new IntentParam(treasury.getScriptHash(), "addFunder",
-                byteArray("3ff68d232a60f23a5805b8c40f7e61747f"), array(asList(alice.getECKeyPair().getPublicKey())));
+                byteArray("3ff68d232a60f23a5805b8c40f7e61747f"), array(Collections.singletonList(alice.getECKeyPair().getPublicKey())));
         String offchainUri = "fail_adding_invalid_funder";
 
         // 1. Create and endorse proposal
@@ -332,9 +323,8 @@ public void fail_adding_invalid_funder() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid funder hash", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid funder hash"));
     }
 
     @Test
@@ -352,9 +342,8 @@ public void fail_adding_funder_with_no_public_keys() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "List of public keys is empty", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("List of public keys is empty"));
     }
 
     @Test
@@ -374,9 +363,8 @@ public void fail_adding_funder_with_invalid_public_key() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid public key", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid public key"));
     }
 
     @Test
@@ -398,12 +386,10 @@ public void fail_setting_funders_multisig_threshold_ratio_with_invalid_value() t
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id1).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid threshold ratio", neow3j);
-        tx = gov.execute(id2).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid threshold ratio", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id1).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid threshold ratio"));
+        e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id2).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid threshold ratio"));
     }
 
     @Test
@@ -422,9 +408,8 @@ public void fail_adding_whitelisted_token_with_invalid_token() throws Throwable
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid token hash", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid token hash"));
     }
 
     @Test
@@ -443,9 +428,8 @@ public void fail_adding_whitelisted_token_with_invalid_max_funding_amount() thro
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Invalid max funding amount", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Invalid max funding amount"));
     }
 
     @Test
@@ -530,9 +514,8 @@ public void fail_adding_already_added_funder() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Already a funder", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Already a funder"));
     }
 
     @Test
@@ -579,9 +562,8 @@ public void fail_removing_nonexistant_funder() throws Throwable {
 
         // 3. Skip till after vote and queued phase, then execute.
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Not a funder", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Not a funder"));
     }
 
     @Test
@@ -765,57 +747,50 @@ public void succeed_pausing_contract() throws Throwable {
     @Order(21)
     @Test
     public void fail_add_funder_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.addFunder(alice.getScriptHash(), alice.getECKeyPair().getPublicKey())
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.addFunder(alice.getScriptHash(), alice.getECKeyPair().getPublicKey()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(22)
     @Test
     public void fail_remove_funder_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.removeFunder(alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.removeFunder(alice.getScriptHash()).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(23)
     @Test
     public void fail_add_whitelisted_token_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.addWhitelistedToken(GasToken.SCRIPT_HASH, 1).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.addWhitelistedToken(GasToken.SCRIPT_HASH, 1).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(24)
     @Test
     public void fail_remove_whitelisted_token_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.removeWhitelistedToken(GasToken.SCRIPT_HASH).signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.removeWhitelistedToken(GasToken.SCRIPT_HASH).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(25)
     @Test
     public void fail_release_tokens_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.releaseTokens(GasToken.SCRIPT_HASH, alice.getScriptHash(), BigInteger.ONE)
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.releaseTokens(GasToken.SCRIPT_HASH, alice.getScriptHash(), BigInteger.ONE).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(26)
     @Test
     public void fail_vote_on_committee_member_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.voteCommitteeMemberWithLeastVotes().signers(AccountSigner.calledByEntry(alice))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.voteCommitteeMemberWithLeastVotes().signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(27)
     @Test
     public void fail_update_contract_on_paused_contract() throws Throwable {
-        Hash256 tx = treasury.updateContract(new byte[]{0x01, 0x02, 0x03}, "the manifest", null)
-                .signers(AccountSigner.calledByEntry(alice)).sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.updateContract(new byte[]{0x01, 0x02, 0x03}, "the manifest", null).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is paused"));
     }
 
     @Order(28)
diff --git a/src/test/java/com/axlabs/neo/grantshares/ProposalExecutionsTest.java b/src/test/java/com/axlabs/neo/grantshares/ProposalExecutionsTest.java
index 57cf3f6..5e10a25 100644
--- a/src/test/java/com/axlabs/neo/grantshares/ProposalExecutionsTest.java
+++ b/src/test/java/com/axlabs/neo/grantshares/ProposalExecutionsTest.java
@@ -10,6 +10,7 @@
 import io.neow3j.test.DeployConfig;
 import io.neow3j.test.DeployConfiguration;
 import io.neow3j.transaction.AccountSigner;
+import io.neow3j.transaction.exceptions.TransactionConfigurationException;
 import io.neow3j.types.CallFlags;
 import io.neow3j.types.ContractParameter;
 import io.neow3j.types.Hash256;
@@ -35,7 +36,6 @@
 import static com.axlabs.neo.grantshares.util.TestHelper.PHASE_LENGTH;
 import static com.axlabs.neo.grantshares.util.TestHelper.PROPOSAL_EXECUTED;
 import static com.axlabs.neo.grantshares.util.TestHelper.REVIEW_LENGTH_KEY;
-import static com.axlabs.neo.grantshares.util.TestHelper.assertAborted;
 import static com.axlabs.neo.grantshares.util.TestHelper.createAndEndorseProposal;
 import static com.axlabs.neo.grantshares.util.TestHelper.prepareDeployParameter;
 import static com.axlabs.neo.grantshares.util.TestHelper.voteForProposal;
@@ -46,6 +46,7 @@
 import static io.neow3j.types.ContractParameter.string;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.core.Is.is;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
 @ContractTest(contracts = GrantSharesGov.class, blockTime = 1, configFile = "default.neo-express",
@@ -76,7 +77,6 @@ public static DeployConfiguration deployConfig() throws Exception {
     @BeforeAll
     public static void setUp() throws Throwable {
         neow3j = ext.getNeow3j();
-        neow3j.allowTransmissionOnFault();
         gov = new GrantSharesGovContract(ext.getDeployedContract(GrantSharesGov.class).getScriptHash(), neow3j);
         alice = ext.getAccount(ALICE);
         bob = ext.getAccount(BOB);
@@ -88,9 +88,8 @@ public static void setUp() throws Throwable {
 
     @Test
     public void fail_executing_non_existent_proposal() throws Throwable {
-        Hash256 tx = gov.execute(1000).signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal doesn't exist", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(1000).signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal doesn't exist"));
     }
 
     @Test
@@ -110,9 +109,8 @@ public void fail_executing_proposal_that_wasnt_endorsed() throws Throwable {
                 .getStack().get(0).getInteger().intValue();
 
         // 2. Call execute
-        tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal not in execution phase", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal not in execution phase"));
     }
 
     @Test
@@ -127,9 +125,8 @@ public void fail_executing_proposal_without_votes() throws Throwable {
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH + PHASE_LENGTH);
 
         // 2. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Quorum not reached", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Quorum not reached"));
     }
 
     @Test
@@ -157,9 +154,8 @@ public void fail_executing_accepted_proposal_multiple_times() throws Throwable {
                 .getNotifications().get(1).getEventName(), is(PROPOSAL_EXECUTED));
 
         // 4. Call execute the second time and fail.
-        tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal already executed", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal already executed"));
     }
 
     @Test
@@ -229,9 +225,8 @@ public void fail_executing_proposal_quorum_reached_but_rejected() throws Throwab
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
         // 3. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal rejected", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal rejected"));
     }
 
     @Test
@@ -253,9 +248,8 @@ public void fail_executing_proposal_quorum_reached_but_all_abstained() throws Th
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
         // 3. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal rejected", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal rejected"));
     }
 
     @Test
@@ -274,9 +268,8 @@ public void fail_executing_proposal_quorum_not_reached() throws Throwable {
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
         // 3. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Quorum not reached", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Quorum not reached"));
     }
 
     @Test
@@ -296,9 +289,8 @@ public void fail_executing_proposal_with_different_quorum_not_reached() throws T
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
         // 3. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Quorum not reached", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Quorum not reached"));
     }
 
     @Test
@@ -320,9 +312,8 @@ public void fail_executing_proposal_with_different_quorum_reached_different_rate
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH);
 
         // 3. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal rejected", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal rejected"));
     }
 
     @Test
@@ -365,8 +356,7 @@ public void fail_executing_expired_proposal() throws Throwable {
         ext.fastForwardOneBlock(PHASE_LENGTH + PHASE_LENGTH + PHASE_LENGTH); // skip voting, time lock, expiration phase
 
         // 2. Call execute
-        Hash256 tx = gov.execute(id).signers(AccountSigner.calledByEntry(bob))
-                .sign().send().getSendRawTransaction().getHash();
-        assertAborted(tx, "Proposal expired", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> gov.execute(id).signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Proposal expired"));
     }
 }
diff --git a/src/test/java/com/axlabs/neo/grantshares/TreasuryMultiSigTest.java b/src/test/java/com/axlabs/neo/grantshares/TreasuryMultiSigTest.java
index fef4a95..34d79f6 100644
--- a/src/test/java/com/axlabs/neo/grantshares/TreasuryMultiSigTest.java
+++ b/src/test/java/com/axlabs/neo/grantshares/TreasuryMultiSigTest.java
@@ -18,6 +18,7 @@
 import io.neow3j.transaction.AccountSigner;
 import io.neow3j.transaction.Transaction;
 import io.neow3j.transaction.Witness;
+import io.neow3j.transaction.exceptions.TransactionConfigurationException;
 import io.neow3j.types.ContractParameter;
 import io.neow3j.types.Hash160;
 import io.neow3j.types.Hash256;
@@ -43,7 +44,6 @@
 import static com.axlabs.neo.grantshares.util.TestHelper.IS_PAUSED;
 import static com.axlabs.neo.grantshares.util.TestHelper.PAUSE;
 import static com.axlabs.neo.grantshares.util.TestHelper.PHASE_LENGTH;
-import static com.axlabs.neo.grantshares.util.TestHelper.assertAborted;
 import static com.axlabs.neo.grantshares.util.TestHelper.createAndEndorseProposal;
 import static com.axlabs.neo.grantshares.util.TestHelper.createMultiSigAccount;
 import static com.axlabs.neo.grantshares.util.TestHelper.prepareDeployParameter;
@@ -53,8 +53,7 @@
 import static java.util.Arrays.asList;
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.core.Is.is;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.*;
 
 @ContractTest(contracts = {GrantSharesGov.class, GrantSharesTreasury.class},
         blockTime = 1, configFile = "default.neo-express", batchFile = "setup.batch")
@@ -117,7 +116,6 @@ public static DeployConfiguration deployConfigTreasury(DeployContext ctx) throws
     @BeforeAll
     public static void setUp() throws Throwable {
         neow3j = ext.getNeow3j();
-        neow3j.allowTransmissionOnFault();
         // contracts
         gov = new GrantSharesGovContract(
                 ext.getDeployedContract(GrantSharesGov.class).getScriptHash(), neow3j);
@@ -183,9 +181,8 @@ public void calc_funders_multisig_address() throws Throwable {
     @Test
     @Order(0)
     public void fail_execute_drain_on_unpaused_contract() throws Throwable {
-        Hash256 tx = treasury.drain().signers(AccountSigner.calledByEntry(alice)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Contract is not paused", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.drain().signers(AccountSigner.calledByEntry(alice)).sign());
+        assertTrue(e.getMessage().endsWith("Contract is not paused"));
     }
 
     @Order(10)
@@ -211,9 +208,8 @@ public void succeed_pausing_contract() throws Throwable {
     @Order(11)
     @Test
     public void fail_execute_drain_with_non_funder() throws Throwable {
-        Hash256 tx = treasury.drain().signers(AccountSigner.calledByEntry(bob)).sign().send()
-                .getSendRawTransaction().getHash();
-        assertAborted(tx, "Not authorized", neow3j);
+        Exception e = assertThrows(TransactionConfigurationException.class, () -> treasury.drain().signers(AccountSigner.calledByEntry(bob)).sign());
+        assertTrue(e.getMessage().endsWith("Not authorized"));
     }
 
     @Order(12)
diff --git a/src/test/java/com/axlabs/neo/grantshares/util/TestHelper.java b/src/test/java/com/axlabs/neo/grantshares/util/TestHelper.java
index f333620..d59c07d 100644
--- a/src/test/java/com/axlabs/neo/grantshares/util/TestHelper.java
+++ b/src/test/java/com/axlabs/neo/grantshares/util/TestHelper.java
@@ -188,12 +188,4 @@ public static Account createMultiSigAccount(int threshold, Account... accounts)
                 .collect(Collectors.toList());
         return Account.createMultiSigAccount(pubKeys, threshold);
     }
-
-    public static void assertAborted(Hash256 tx, String expectedError, Neow3j neow3j) throws IOException {
-        Await.waitUntilTransactionIsExecuted(tx, neow3j);
-        NeoApplicationLog.Execution e = neow3j.getApplicationLog(tx).send().getApplicationLog().getExecutions().get(0);
-        assertThat(e.getState(), is(NeoVMStateType.FAULT));
-        String exception = e.getNotifications().get(0).getState().getList().get(0).getString();
-        assertThat(exception, containsString(expectedError));
-    }
 }