InternalServerErrorException: 500#

So it seems there is a succes answer form webservice but then it fails

Ifs.Fnd.FndSystemException: Utforsker: Et unntak som ikke håndteres har oppstått ---> Ifs.Fnd.FndSystemException: Unexpected error while calling server method ConnectTester/TestRouteAddress ---> Ifs.Fnd.FndServerFaultException: Exception while sending data 
Caused by: ifs.fnd.connect.http.InternalServerErrorException: InternalServerErrorException: 500#Det har skjedd en teknisk feil
   ved Ifs.Fnd.AccessProvider.FndConnection.ParseErrorHeader(FndBuffer buffer, FndManualDecisionCollection decisions)
   ved Ifs.Fnd.AccessProvider.FndConnection.UnMarshalResponseHeader(Stream responseStream, FndManualDecisionCollection decisions)
   ved Ifs.Fnd.AccessProvider.FndConnection.HandleHttpSuccessResult(HttpWebResponse result, FndManualDecisionCollection decisions, String operation, FndBodyType responseBodyType, Object responseBody)
   ved Ifs.Fnd.AccessProvider.FndConnection.InvokeInternal(Object requestBody, Object responseBody, String intface, String operation, FndRequestContext requestContext, FndManualDecisionCollection decisions, Boolean forcedSync, Boolean integrationGateway)
   --- Slutten på sporingen av intern unntaksstakk ---
   ved Ifs.Fnd.AccessProvider.FndConnection.InvokeInternal(Object requestBody, Object responseBody, String intface, String operation, FndRequestContext requestContext, FndManualDecisionCollection decisions, Boolean forcedSync, Boolean integrationGateway)
   ved Ifs.Fnd.AccessProvider.FndConnection.InvokeInternal(String intface, String operation, Object requestBody, Object responseBody, FndRequestContext requestContext, Boolean forcedSync, Boolean integrationGateway)
   ved Ifs.Fnd.AccessProvider.Activity.FndActivityContext.InvokeIntegration(String intface, String operation, Object request, Object response)
   ved Ifs.Fnd.AccessProvider.Activity.FndActivityCommand.ExecuteNonQuery(Object body)
   ved Ifs.Application.MessageRouting.ServerInterface.Ifs.Application.MessageRouting.IConnectTester.TestRouteAddress(RouteAddress address, ApplicationMessage& message)
   ved Ifs.Application.MessageRouting.TestRouteAddress.fndButtonSend_Click(Object sender, EventArgs e)
   ved System.Windows.Forms.Control.OnClick(EventArgs e)
   ved System.Windows.Forms.Button.OnClick(EventArgs e)
   ved Ifs.Fnd.Windows.Forms.FndButton.OnClick(EventArgs e)
   ved System.Windows.Forms.Button.WndProc(Message& m)
   ved System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
   ved System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
   ved System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)