Right Click tab on worksheet where your data is entered, "view code" and
copy/paste this code. Assumes entries are in Columns A & B.

HTH


Private Sub Worksheet_Change(ByVal Target As Range)
On Error GoTo ws_exit
Application.EnableEvents = False
If Target.Column < 3 Then
If Cells(Target.Row, "A") = Cells(Target.Row, "B") Then
MsgBox "To/From cannot be same location"
End If
End If
ws_exit:
Application.EnableEvents = True
End Sub

"Zilla" wrote:

I want to tabulate a From-To places list
to signify trips FromA-ToB.

Say I have col A validated against a list that
signifies the "From". Col B is also validated
with the same list, that signifies the "To".
Obviously, I don't want Col A and Col B
be the same value for the same row since
FromA-ToA does not make sense.

How can I do this in VBA, or vanilla Excel?

--
- Zilla
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