What can cause a form to lose its link to its parent form in an MDI vb.net project?

Question

Very periodically, some of our forms in our MDI vb.net project will return me.parent as nothing. I've never seen this while debugging, but it does cause an un-handled exception on our client machines - and the form that they have open varies from case to case.

Is there any sort of event, short of a 'me.parent = nothing', that can cause this link to be broken?

Answer 1

Freakin' users.

It looks like this is replicated by closing the current form before the new form can be opened. (In my case, while a report is generating) The little hour-glass icon wasn't apparently deterrent enough.