Tom-

>>Are you using a framework?
>
>Yes we are using Visual Extend.

Does the framework use a standard edit command button...I'm thinking there may be code in the framework that is resetting the readonly flags depending on what edit mode you are in.

I would probably start with a sample grid with just one of the problem fields in it. Then put a breakpoint in the gotfocus of the textbox (you can add a DODEFAULT() and put a BP on that line), and check the readonly flag of the textbox and the column.