i have which is i fond in net

please let me know how can i modify this code

this undo code should work
After Running Other Macro Codes 



Private Sub Worksheet_Change(ByVal Target As Range)






    'set your criteria here
    If Target.Column < 16 Then

        'must disable events if you change the sheet as it will
        'continually trigger the change event
         Application.EnableEvents = False
         Application.Undo
         Application.EnableEvents = True

         MsgBox "You cannot do that!"
       
     End If
End Sub