diff --git a/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfig.java b/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfig.java
index e41c0ccd1..3a27c24d8 100644
--- a/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfig.java
+++ b/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfig.java
@@ -345,7 +345,7 @@ public String getOauthUrl() {
    * (called only if authentication method is OAUTH2)
    */
   public String getExternalOauthUrl() {
-    return _externalOauthUrl == null || _externalOauthUrl.isBlank() ? _externalOauthUrl : _oauthUrl;
+    return _externalOauthUrl != null && !_externalOauthUrl.isBlank() ? _externalOauthUrl : _oauthUrl;
   }
 
   /**
diff --git a/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfigBuilder.java b/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfigBuilder.java
index 54f0bc250..5e11ce676 100644
--- a/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfigBuilder.java
+++ b/Model/src/main/java/org/gusdb/wdk/model/config/ModelConfigBuilder.java
@@ -59,7 +59,7 @@ public class ModelConfigBuilder {
   // user authentication setup
   private AuthenticationMethod _authenticationMethod = AuthenticationMethod.USER_DB;
   private String _oauthUrl = ""; // needed if method is OAUTH2
-  private String _externalOauthUrl = ""; // may be needed if method is OAUTH2 and internal URL is not available externally
+  private String _externalOauthUrl = null; // may be needed if method is OAUTH2 and internal URL is not available externally
   private String _oauthClientId = ""; // needed if method is OAUTH2
   private String _oauthClientSecret = ""; // needed if method is OAUTH2
   private String _changePasswordUrl = ""; // probably needed if method is OAUTH2