I am tying to set up an input mask for a textbox in a userfrom.

The user will only be able to enter a 12 character string.
The string will look like GSSL########
All entries into this box must have GSSL at the beginning,
and the ######## represents any 8 digit number.

Is this even possible in Excel.

I have been trying to crack this for some time.

I am extremly new to VBA and i could be missing something simple.

Any help appriciated.
Axe.