Pattern field problem

Having a patern field to change case of the data entered, my users first have to delete a series of blank characters in the field before entering data, it is a 25 character long field and I have populated the Edit mask field with 25 capital X’s, am I doing something wrong?

Not doing anything wrong. If the field is tabbed to in a new (or previously blank) entry, the blanks which appear with blue selected area are the number of characters for the entry as declared in your Edit Mask. If data entry is started with the blue selected area showing, characters will begin entry in the leftmost position and in the case where data was there already, it will be completely overwritten. If, however you go to the control via mouse, the cursor will be at the position it was clicked. You can hit the Home key and the cursor will be at the leftmost position. Data may be entered without deleting anything.

thanks for that, as it is the first field on the form I wil add another field before it so the user will tab into the field in question.

You don’t need to do that. In edit mode, make sure it is the first field in the Activation Order (Tab order) and then while that field is selected, turn on Automatic Control Focus using the icon in the Form Design toolbar.