>Have you checked to see if the VFP runtime version is correct?

yes...Hey, just found the problem by inspecting code carefully. There's an SQL into cursor in the modal form's activate(), the cursor is made writeable. After this, there are some Inserts done. There is the wrong number of parameters in the Insert! Once I thought about the error, it dawned on me where to look...

Why the heck this doesn't cause an error on 30 or more machines is beyond me. The one woman's machine is more sensitive, I guess :) Anyway thanks, for input...