Hi Mark,
Not for me. I have several prg based classes (used in grids) where the control's parentclass is a visual class..., but after testing, you are right. (I thought you had to put some extension!) If a VCX and PRG have the same file name (less extension), VFP defaults to the PRG/FXP. So if one wishes to base a prg defined class on a vcx defined class, one should include the VCX extension to avoid ambiguity.

>I just do not include the file extension and all works just fine. The OF ClassLib is always a PRG/FXP based file.
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