Eric,
If SP3 doesn't solve the problem, make sure that you don't have a case where any of your classes have added a PEM that is now part of the PEM set for the VFP6 classes. You might also try an explicit COMPILE CLASSLIB for each of your classlibs before editting the form. You might also COMPILE FORM.
Does the form have an ActiveX control on it?
>I forms working fine in 5.0
>
>I try to open them in 6.0 and get the following error message :
>
>"Fatal Error Exception Code C0000005"
>
>
>Any ideas?