>Thank, that helps after I have made the error. What I was hoping was that there might be some way to stop myself from getting that far. A freind told me that they heard of some way to set on some bits in the header of the FP2.6 files which generates an error when you try to modify from VFP. Of course he couldn't rember which bits in what byte or even where he heard it.

Keep SET EXCLUSIVE OFF and you will never change table structure.
Best regards to your friend :-).