Private Sub Workbook_Open()
'bloquer si date en R1< date du jour
Dim wks As Worksheet
For Each wks In Worksheets
If Left(wks.Name, 3) = "sem" Then
If wks.Range("R1").Value < Date Then
wks.Protect
'Range("C4:S14").Locked = True
Else
wks.Unprotect
End If
End If
Next
End Sub