Sub Macro1()
On Error Resume Next
Sheets.Add(After:=Worksheets(Worksheets.Count)).Name = Format(Date, "WW")
If Err Then
MsgBox "Sauvegarde déjà effectuée !?", vbExclamation, ""
Else
MsgBox "Sauvegarde Semaine Ok", vbInformation
End if
On Error GoTo 0: Err.Clear
End Sub