Sub Creer_copie()
On Error Resume Next
Workbooks("Copie de " & ThisWorkbook.Name & ".xlsm").Close 'si le classeur est ouvert on le ferme
ThisWorkbook.SaveCopyAs ThisWorkbook.Path & "\Copie de " & ThisWorkbook.Name & ".xlsm"
Workbooks.Open ThisWorkbook.Path & "\Copie de " & ThisWorkbook.Name & ".xlsm"
End Sub