A way you could Achieve what you want is to use something like this
Code
-------------------
Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Row = 1 And Target.Column = 1 Then
Select Case Target.Formula
Case "A"
'allow this
Case ""
'allow this
Case Else
'reset to nothing
Target.Formula = ""
End Select
End If
End Sub
-------------------
this validates the value of A1 after the user leaves the cell.
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments. After that, you can post your question and our members will help you out.