Hi Phil,
Give this a try on your sheet level code
Code:
Private Sub Worksheet_Change(ByVal Target As Range)
If Target.CountLarge > 1 Then Exit Sub
If Not Intersect(Target, Range("A2:AS21")) Is Nothing Then
Cells(Target.Row, 46).Value = Format(Now, "mm/dd/yyyy")
End If
End Sub
Since you want this date in column AT, I changed the target range to only go thru AS