diff --git a/.azure-pipelines/azure-pipelines-win.yml b/.azure-pipelines/azure-pipelines-win.yml
index bf71b962d14..f577e1b4663 100644
--- a/.azure-pipelines/azure-pipelines-win.yml
+++ b/.azure-pipelines/azure-pipelines-win.yml
@@ -52,6 +52,7 @@ jobs:
 
   - powershell: ./tools/azure-devops/win/install.ps1
     displayName: Install Requirements
+    errorActionPreference: continue # Errors are handled in the script
   - powershell: ./tools/azure-devops/win/build.ps1
     displayName: "Build: $(CC_NAME)"
     errorActionPreference: continue # If set to Stop, we only get a truncated exception message. Error is handled by checking exit code
@@ -83,6 +84,7 @@ jobs:
 
   - powershell: ./tools/azure-devops/win/install.ps1
     displayName: Install Requirements
+    errorActionPreference: continue # Errors are handled in the script
   - powershell: ./tools/azure-devops/win/build.ps1
     displayName: "Build: $(CC_NAME)"
     errorActionPreference: continue # If set to Stop, we only get a truncated exception message. Error is handled by checking exit code
diff --git a/src/pubsub/ua_pubsub_writer.c b/src/pubsub/ua_pubsub_writer.c
index fb408ace904..691a7fbd445 100644
--- a/src/pubsub/ua_pubsub_writer.c
+++ b/src/pubsub/ua_pubsub_writer.c
@@ -1218,6 +1218,10 @@ UA_Server_addDataSetWriter(UA_Server *server,
             return UA_STATUSCODE_BADOUTOFMEMORY;
         }
         newDataSetWriter->lastSamplesCount = currentDataSetContext->fieldSize;
+        for(size_t i = 0; i < newDataSetWriter->lastSamplesCount; i++) {
+            UA_DataValue_init(&newDataSetWriter->lastSamples[i].value);
+            newDataSetWriter->lastSamples[i].valueChanged = false;
+        }
     }
 #endif
 
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 7cc9868658e..2840d69beaa 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -398,11 +398,11 @@ if(UA_ENABLE_PUBSUB)
     if(UA_ENABLE_PUBSUB_INFORMATIONMODEL)
         add_executable(check_pubsub_informationmodel pubsub/check_pubsub_informationmodel.c $<TARGET_OBJECTS:open62541-object> $<TARGET_OBJECTS:open62541-plugins>)
         target_link_libraries(check_pubsub_informationmodel ${LIBS})
-        add_test(check_pubsub_informationmodel ${TESTS_BINARY_DIR}/check_pubsub_informationmodel)
+        add_test_valgrind(check_pubsub_informationmodel ${TESTS_BINARY_DIR}/check_pubsub_informationmodel)
         if(UA_ENABLE_PUBSUB_INFORMATIONMODEL_METHODS)
             add_executable(check_pubsub_informationmodel_methods pubsub/check_pubsub_informationmodel_methods.c $<TARGET_OBJECTS:open62541-object> $<TARGET_OBJECTS:open62541-plugins>)
             target_link_libraries(check_pubsub_informationmodel_methods ${LIBS})
-            add_test(check_pubsub_informationmodel_methods ${TESTS_BINARY_DIR}/check_pubsub_informationmodel_methods)
+            add_test_valgrind(check_pubsub_informationmodel_methods ${TESTS_BINARY_DIR}/check_pubsub_informationmodel_methods)
 
         endif()
     endif()
diff --git a/tests/client/check_client_subscriptions.c b/tests/client/check_client_subscriptions.c
index 99e81a8bdd3..414b13baecb 100644
--- a/tests/client/check_client_subscriptions.c
+++ b/tests/client/check_client_subscriptions.c
@@ -42,8 +42,10 @@ static void setup(void) {
 }
 
 static void teardown(void) {
-    running = false;
-    THREAD_JOIN(server_thread);
+    if (running) {
+        running = false;
+        THREAD_JOIN(server_thread);
+    }
     UA_Server_run_shutdown(server);
     UA_Server_delete(server);
 }
diff --git a/tools/azure-devops/win/build.ps1 b/tools/azure-devops/win/build.ps1
index 44bbf808d42..aded74aaac1 100644
--- a/tools/azure-devops/win/build.ps1
+++ b/tools/azure-devops/win/build.ps1
@@ -47,6 +47,40 @@ try {
     Copy-Item AUTHORS pack
     Copy-Item README.md pack
 
+    # Only execute unit tests on vs2017 to save compilation time
+    if ($env:CC_SHORTNAME -eq "vs2017") {
+        Write-Host -ForegroundColor Green "`n###################################################################"
+        Write-Host -ForegroundColor Green "`n##### Testing $env:CC_NAME with unit tests #####`n"
+        New-Item -ItemType directory -Path "build"
+        cd build
+        & cmake $cmake_cnf `
+                -DBUILD_SHARED_LIBS:BOOL=OFF `
+                -DCMAKE_BUILD_TYPE=Debug `
+                -DUA_BUILD_EXAMPLES=OFF `
+                -DUA_BUILD_UNIT_TESTS=ON `
+                -DUA_ENABLE_DA=ON `
+                -DUA_ENABLE_DISCOVERY=ON `
+                -DUA_ENABLE_DISCOVERY_MULTICAST=ON `
+                -DUA_ENABLE_ENCRYPTION:BOOL=$build_encryption `
+                -DUA_ENABLE_JSON_ENCODING:BOOL=ON `
+                -DUA_ENABLE_PUBSUB:BOOL=ON `
+                -DUA_ENABLE_PUBSUB_DELTAFRAMES:BOOL=ON `
+                -DUA_ENABLE_PUBSUB_INFORMATIONMODEL:BOOL=ON `
+                -DUA_ENABLE_UNIT_TESTS_MEMCHECK=ON ..
+        & cmake --build . --config Debug
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Make failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
+        & cmake --build . --target test-verbose --config Debug -j 1
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Make failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
+        cd ..
+        Remove-Item -Path build -Recurse -Force
+    }
+
     Write-Host -ForegroundColor Green "`n###################################################################"
     Write-Host -ForegroundColor Green "`n##### Testing $env:CC_NAME with amalgamation #####`n"
     New-Item -ItemType directory -Path "build"
@@ -55,6 +89,7 @@ try {
             -DCMAKE_BUILD_TYPE=RelWithDebInfo `
             -DUA_BUILD_EXAMPLES:BOOL=OFF  `
             -DUA_ENABLE_AMALGAMATION:BOOL=ON `
+            -DUA_ENABLE_SUBSCRIPTIONS_EVENTS:BOOL=ON `
             -DUA_ENABLE_ENCRYPTION:BOOL=$build_encryption ..
     & cmake --build . --config RelWithDebInfo
     if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
@@ -79,7 +114,7 @@ try {
             -DUA_ENABLE_PUBSUB_INFORMATIONMODEL:BOOL=ON `
             -DUA_ENABLE_SUBSCRIPTIONS_EVENTS:BOOL=ON `
             -DUA_NAMESPACE_ZERO:STRING=FULL ..
-    & cmake --build . --config RelWithDebInfo
+    & cmake --build . --config Debug
     if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
         Write-Host -ForegroundColor Red "`n`n*** Make failed. Exiting ... ***"
         exit $LASTEXITCODE
@@ -137,37 +172,6 @@ try {
     }
     Remove-Item -Path build -Recurse -Force
 
-    # Only execute unit tests on vs2017 to save compilation time
-    if ($env:CC_SHORTNAME -eq "vs2017") {
-        Write-Host -ForegroundColor Green "`n###################################################################"
-        Write-Host -ForegroundColor Green "`n##### Testing $env:CC_NAME with unit tests #####`n"
-        New-Item -ItemType directory -Path "build"
-        cd build
-        & cmake $cmake_cnf `
-                -DBUILD_SHARED_LIBS:BOOL=OFF `
-                -DCMAKE_BUILD_TYPE=Debug `
-                -DUA_BUILD_EXAMPLES=OFF `
-                -DUA_BUILD_UNIT_TESTS=ON `
-                -DUA_ENABLE_DA=ON `
-                -DUA_ENABLE_DISCOVERY=ON `
-                -DUA_ENABLE_DISCOVERY_MULTICAST=ON `
-                -DUA_ENABLE_ENCRYPTION:BOOL=$build_encryption `
-                -DUA_ENABLE_JSON_ENCODING:BOOL=ON `
-                -DUA_ENABLE_PUBSUB:BOOL=ON `
-                -DUA_ENABLE_PUBSUB_DELTAFRAMES:BOOL=ON `
-                -DUA_ENABLE_PUBSUB_INFORMATIONMODEL:BOOL=ON `
-                -DUA_ENABLE_UNIT_TESTS_MEMCHECK=ON ..
-        & cmake --build . --config Debug
-        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
-            Write-Host -ForegroundColor Red "`n`n*** Make failed. Exiting ... ***"
-            exit $LASTEXITCODE
-        }
-        & cmake --build . --target test-verbose --config Debug
-        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
-            Write-Host -ForegroundColor Red "`n`n*** Make failed. Exiting ... ***"
-            exit $LASTEXITCODE
-        }
-    }
 
     # # do not cache log
     # Remove-Item -Path c:\miktex\texmfs\data\miktex\log -Recurse -Force
diff --git a/tools/azure-devops/win/install.ps1 b/tools/azure-devops/win/install.ps1
index 8c9513ce1a3..85b367c1d06 100644
--- a/tools/azure-devops/win/install.ps1
+++ b/tools/azure-devops/win/install.ps1
@@ -1,36 +1,53 @@
-$ErrorActionPreference = "Stop"
-
 try {
 
     Write-Host -ForegroundColor Green "`n### Installing sphinx ###`n"
     & choco install -y sphinx --no-progress --source python
+    if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+        Write-Host -ForegroundColor Red "`n`n*** Install failed. Exiting ... ***"
+        exit $LASTEXITCODE
+    }
 
     if ($env:CC_SHORTNAME -eq "mingw" -or $env:CC_SHORTNAME -eq "clang-mingw") {
         Write-Host -ForegroundColor Green "`n### Installing msys64 ###`n"
-        # Install specific version of msys2. See https://github.com/open62541/open62541/issues/3233
-        & choco install -y msys2 --version 20180531.0.0 --no-progress --params="/InstallDir:$env:MSYS2_ROOT /NoUpdate /NoPath"
+        & choco install -y msys2 --no-progress --params="/InstallDir:$env:MSYS2_ROOT /NoUpdate /NoPath"
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Install failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
 
         Write-Host -ForegroundColor Green "`n### Installing mbedtls via PacMan ###`n"
         # pacman may complain that the directory does not exist, thus create it.
         # See https://github.com/open62541/open62541/issues/2068
         & C:\msys64\usr\bin\mkdir -p /var/cache/pacman/pkg
-        & cmd /c 'C:\\msys64\\usr\\bin\\pacman 2>&1' --noconfirm --needed -S mingw-w64-x86_64-mbedtls
+        & C:\msys64\usr\bin\pacman --noconfirm --needed -S mingw-w64-x86_64-mbedtls
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Install failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
 
-        Write-Host -ForegroundColor Green "`n### Installing clang via PacMan ###`n"
-        & cmd /c 'C:\\msys64\\usr\\bin\\pacman 2>&1' --noconfirm --needed -S mingw-w64-x86_64-clang mingw-w64-i686-clang
     } elseif ($env:CC_SHORTNAME -eq "vs2015" -or $env:CC_SHORTNAME -eq "vs2017") {
         Write-Host -ForegroundColor Green "`n### Installing mbedtls via vcpkg ###`n"
         & vcpkg install mbedtls:x86-windows-static
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Install failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
 
         Write-Host -ForegroundColor Green "`n### Installing libcheck via vcpkg ###`n"
         & vcpkg install check:x86-windows-static
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Install failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
 
         Write-Host -ForegroundColor Green "`n### Installing DrMemory ###`n"
-        # 12. March 2020: Hardcode Dr Memory Version to 2.2. Otherwise it fails with
-        # "Failed to take over all threads after multiple attempts."
-        # See: https://dev.azure.com/open62541/open62541/_build/results?buildId=1242&view=logs&j=0690d606-4da6-5fc6-313c-2fce474be087&t=6290dcff-a4f0-5630-9345-7cbc0279a890&l=1871
-        & choco install -y --no-progress drmemory.portable --version 2.2.0
-        $env:Path = 'C:\Program Files (x86)\Dr. Memory\bin;' + $env:Path        
+        & choco install -y --no-progress drmemory.portable
+        if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {
+            Write-Host -ForegroundColor Red "`n`n*** Install failed. Exiting ... ***"
+            exit $LASTEXITCODE
+        }
+        #$env:Path = 'C:\Program Files (x86)\Dr. Memory\bin;' + $env:Path
+        #[System.Environment]::SetEnvironmentVariable('Path', $path, 'Machine')
     }
 
     if ($LASTEXITCODE -and $LASTEXITCODE -ne 0) {