Hello, i made tons of apps in vb6 using this command structure:

blah blah...

Form5.Show 1 'show some modal dialog, it returns a value for a variable 'UserSelection'
Select Case UserSelection
Case 1: blah blah
Case 2: blah blah
End Select
SomeOtherForm.Show 'non modal form to be displayed

In Windows XP, no problem at all. My client has Windows 7 and some times, not all times, it returns an error message saying "Cant display non modal form when modal form is displayed".
How this can be wrong in Windows 7 ONLY ? When Form5 is displayed, the instruction pointer stop there until the form finishes and after unloads then goes to the Select-Case and then displayes the non modal form.

Whats wrong in Windows 7? Some incombatibility? The Form5 has no special objects, just a listbox and two buttons Accept/Cancel. No timer objects.