Option Explicit
Sub Ouvrir()
Dim Fichier As String
Fichier = "C:\Users\" & Environ("Username") & "\Documents\Classeur1.xlsm"
Workbooks.Open Filename:=Fichier, WriteResPassword:="titi"
With ActiveWorkbook
.Sheets("Feuil1").Activate
ActiveSheet.Unprotect ("toto")
End With
End Sub