diff --git a/dotnet/src/dotnetcore/GxClasses.Web/Middleware/GXRestServices.cs b/dotnet/src/dotnetcore/GxClasses.Web/Middleware/GXRestServices.cs
index e41343e7e..17bb3d5b4 100644
--- a/dotnet/src/dotnetcore/GxClasses.Web/Middleware/GXRestServices.cs
+++ b/dotnet/src/dotnetcore/GxClasses.Web/Middleware/GXRestServices.cs
@@ -271,7 +271,7 @@ protected bool IsAuthenticated(string synchronizer)
 			finally
 			{
 				if (!validSynchronizer)
-					HttpHelper.SetError(HttpContext, "0", "Invalid Synchronizer " + synchronizer);
+					_errorDetail = HandleError("0", "Invalid Synchronizer " + synchronizer);
 			}
 		}
 		protected bool IsAuthenticated()