I had the same problem when I upgraded from VFP5 to VFP6. Someone on the UT gave me this answer and it worked very well for me.

Check the field RESERVED5. I had some garbage into it.

USE MyClass.vcx EXCL
BROW

Delete the garbage in RESERVED5 (it is a memo field, so it's easy to see if there is garbage).

COMPILE CLASS


Hope this will help,
Christian Cote