what about this ?

is this a possible code to prevent typing a letter ?

code : text1_change
if val(text1.text),(len(text1.text)-1))=0 _
and mid(text1.text),(len(text1.text)-1)) <> 0 then
command1.enable = false

thanks for reading :)
lllld_bllll

One trick is to use the KeyPress event;

Sub TextBox1_KeyPress(KeyAscii As Integer)
If KeyAscii = ASC("B") Then KeyAscii = 0
End Sub

Now the user cannot type a capital B into the box. This doesn't prevent them copying and pasting one in though.