The Workflow Manager Backend service crashes intermittently with the following exception:
Dispatcher encountered an unexpected exception: System.Xaml.XamlObjectWriterException: Cannot set unknown member
at System.Xaml.XamlObjectWriter.WriteStartMember(XamlMember property)
at System.Xaml.XamlServices.Transform(XamlReader xamlReader, XamlWriter xamlWriter, Boolean closeWriter)
at System.Activities.XamlIntegration.FuncFactory`1.Evaluate()
at System.Activities.DynamicActivity.OnInternalCacheMetadata(Boolean createEmptyBindings)
at System.Activities.Activity.InternalCacheMetadata(Boolean createEmptyBindings, IList`1& validationErrors)
at System.Activities.ActivityUtilities.ProcessActivity(ChildActivity childActivity, ChildActivity& nextActivity, Stack`1& activitiesRemaining, ActivityCallStack parentChain, IList`1& validationErrors, ProcessActivityTreeOptions options, ProcessActivityCallback callback)
at System.Activities.ActivityUtilities.ProcessActivityTreeCore(ChildActivity currentActivity, ActivityCallStack parentChain, ProcessActivityTreeOptions options, ProcessActivityCallback callback, IList`1& validationErrors)
at System.Activities.ActivityUtilities.CacheRootMetadata(Activity activity, LocationReferenceEnvironment hostEnvironment, ProcessActivityTreeOptions options, ProcessActivityCallback callback, IList`1& validationErrors)
at System.Activities.Hosting.WorkflowInstance.ValidateWorkflow(WorkflowInstanceExtensionManager extensionManager)
at System.Activities.Hosting.WorkflowInstance.RegisterExtensionManager(WorkflowInstanceExtensionManager extensionManager)
at Microsoft.Activities.Hosting.HostedWorkflowInstance.RegisterExtensions(IEnumerable`1 extensions)
at Microsoft.Activities.Hosting.WorkflowSession.ConfigureEnvironment(Activity workflowDefinition, IWorkflowConfiguration workflowConfiguration, IEnumerable`1 hostExtensions)
at Microsoft.Activities.Dispatcher.DispatchLoopInstanceAsyncResult.ConfigureSession(WorkflowSessionResumptionContext context)
at Microsoft.Activities.Dispatcher.DispatchLoopInstanceAsyncResult.GotResumptionContextForProcessWaiter(IAsyncResult result)
at Microsoft.Activities.Dispatcher.DispatchLoopInstanceAsyncResult.Isolate(AsyncCompletion callback, IAsyncResult result)
at Microsoft.Activities.Dispatcher.DispatchLoopInstanceAsyncResult.ExceptionHandlingFrame(IAsyncResult result)
The intermittent issue occurs when using remote database or SQL Azure for Workflow Manager farm. The update fixes an issue with a user-defined table type in workflow instance management database.
Failover issue when using SQL Always On feature.
Starting this update Workflow Manager handles the transient exceptions from SQL when Always On failover is in progress.
Modifying the SQL Collation for Workflow Manager farm databases fails.
Fixed capitalization of one of the stored procedures because it causes an issue when the SQL collation is case sensitive.
Get-WFFarm cmdlet reports an incorrect certificate thumbprint.
After rolling over the Workflow Manager farm certificates the cmdlet points an incorrect certificate thumbprint as one of the farm databases still has a reference to an old thumbprint. Starting this update, the cmdlet reports the new thumbprint.
Workflow Manager Client goes into an unhealthy state.
One of the exceptions in Workflow Manager Client while preparing content of the HTTP request is not handled and that can eventually exhaust the number of free connections in the connection pool used by the client. This can result in Workflow Manager Client communication issues with Workflow Manager Server. This update fixes the client to close the request stream to release the connection back to the pool for reuse.