Protection à la fermeture.

Sub ProtegeTout()
Dim feuil

For Each feuil In Application.Sheets

feuil.Protect Password:="tonmotdepasse", DrawingObjects:=True, Contents:=True, Scenarios:=True _
        , AllowFormattingCells:=True

Next feuil

End Sub

Sub DeprotegeTout()
Dim feuil

For Each feuil In Application.Sheets

feuil.Unprotect Password:="tonmotdepasse"

Next feuil

End Sub

Sub MasquerColonne()

    Sheets("Feuil1").Select
    Columns("A:B").Select
    Selection.ColumnWidth = 0
    Sheets("Feuil2").Select

End Sub

Private Sub Workbook_Open()

Application.DisplayAlerts = False
Application.ScreenUpdating = False

    Module1.MasquerColonne
    Module1.ProtegeTout    
    Sheets("Feuil2").Select

Application.ScreenUpdating = True
Application.DisplayAlerts = true
End Sub
Private Sub Workbook_Close()

Application.ScreenUpdating = False

    Module1.MasquerColonne
    Module1.ProtegeTout    
    Sheets("Feuil2").Select

Application.ScreenUpdating = True

End Sub