>>>using the project manager or 'modify form ...' gives me a dialog 'Syntax error', 'OK' or 'Help'. Click 'OK' : dialog disappears and that's it. Form doesn't show at all ...
>>
>>Do you have = in front of form's Caption in properties sheet? Do you still have VFP5? If so, put a space before = and see, if it helps.

This doesn't seem to be the problem.

It seems that the problem occurs with all the forms that inherit from a base fromset I have in a class. But I can open the baseclass correctly.

Other forms that do no use this particlar basefromset open correctly ...