>Thanks for your reply. Actually I found a cause and a temporary solution in the registry. One of the VFP settings was -32000 for row and column. When I manually reset the values to something reasonable, the problem went away...temporarily. Apparently something on the system is re-setting those row and column settings to bogus values.

It did happen to me once a couple month ago. I deleted those registry keys and VFP works fine since them.