>I want to make the field readonly so that the foxpro application cannot make any changes to it.
>The bigger problem is that something in the foxpro application is deleting the contents of that field. That field is customer number and it is in the master customers table. The users tell me some of the customer numbers are getting deleted every once in awhile. They say no one is deleting them. I looked through the application code for references to customer number and have not found any spots where it could be getting deleted. So I want to make customer number readonly as a start. Any other ideas you have would be helpful.

Are you using free tables or are you using DBCs with views? If you're using DBCs, are you accessing tables through views or are you accessing the table directly?
How are you implementing your edit screens? If you've got a grid control on a form they could cause unexpected change to current workarea whenever they have focus. I don't recall if BROWSE does the same, but I suspect they will behave similarly to grid controls (I hadn't used BROWSE in programs since moving from FPD/FPW to VFP, as they were always tricky to deal with and didn't integrate well with forms anyway).