Private Sub Worksheet_Change(ByVal Target As Range)
Dim Message As String, cel As Range
Application.EnableEvents = False
If IsEmpty( [S23]) Then
Exit Sub
Message = ""
Else
If Weekday( [S23], vbMonday) = 4 And [N23] = 12 Then Message = "CP Jeudi après Midi non autorisée"
If Weekday( [S23], vbMonday) = 5 Then Message = "Attention c'est un Vendredi!"
If Weekday( [S23], vbMonday) = 6 Then Message = "Attention c'est Samedi!"
If Weekday( [S23], vbMonday) = 7 And [N23] = 8 Then Message = " CP Dimanche Matin Non Autorisée"
Call MsgBox("" _
& Message & vbCrLf & "" _
, vbExclamation, "Selon le règlement interne")
End If
Application.EnableEvents = True
End Sub