Private Sub Worksheet_Change(ByVal Target As Range)
If Intersect(Target, [D:G]) Is Nothing Or Target.Count > 1 Then Exit Sub
Dim Cel As Range, ref$
Application.EnableEvents = False
Set Cel = ActiveCell
Application.Undo
ref = ActiveCell.Formula
Application.Undo
If ref <> "" And Target.Formula <> ref Then Range("I" & Target.Row) = "modif"
Cel.Select
Application.EnableEvents = True
End Sub