I have a business object (CustomerBO) that I’ve configured to raise a single property changed event for all properties. I’ve placed this BO on a SF maintenance form. The maintenance form also includes a ChildFormDialog that maps CustomerBO to the dialog form. If I add the FieldPropertyChanged event handler to the maintenance form code, I get an invalid operation exception (see attached) when I attempt to show the ChildFormDialog. If the FieldPropertyChanged event handler is not present on the maintenance form, the ChildFormDialog executes okay.  The FieldPropertyChanged event handler doesn’t have to contain any code to cause the error.

-Larry

Yeah, I'm glad we got this one fixed as well.  As for the other problem... it might be some sort of PInvoke problem.  It looks from your samples that the C# MDAs are catching the exception while the VB.NET ones aren't, so I'm going to see if I can reproduce it in C#.  I'll keep you posted.