During migratio of a simple project, we found an interesting migration details.
The solution has a project with two Forms. Form1 and Form2. Form1 has a command button and in the Click for that command button it performs a code like UnLoad Form2.
But it could happen that Form2 has not been loaded but in VB6 it is not a problem. In .NET the code will be something like form2.Close() and it could cause problems.
A possible fix is to add some flag that indicates if the form was instanciated and the call the event.