>Kev,
>Are you sure you don't have any code in the base class for the TextBox maybe LostFocus or Valid?

There is code in the Valid/LostFocus but nothing that should effect it.

>Try testing the code on a clean form with a clean TextBox (ie use Fox classes) just to see how your code should react.

Yeah it works fine with Base classes.

I shall double-check my class code and get back to you.

Thanks
Kev