The workflow file name extension is not valid. The workflow file name {0} that is listed in the WorkflowsToProcess key of ...

The workflow file name extension is not valid. The workflow file name {0} that is listed in the WorkflowsToProcess key of the module manifest does not have the required .XAML or .DLL file name extension. Edit the module manifest and correct the workflow file name. If you are using a .DLL file extension, then provide only one assembly name.