VBA recherche dans un classeur fermé

Private Sub ComboBox1_Change()

Dim cb1 As String 'déclare la variable cb1 (ComboBox1)
Dim cb3 As String 'déclare la variable cb3 (ComboBox3)

cb1 = ComboBox1.Value 'définit la variable cb1
cb3 = ComboBox3.Value 'définit la variable cb3

Dim Ws As Worksheet
  
Dim fichier As String, wb As Workbook
fichier = ThisWorkbook.Path & "\" & cb3 & ".xlsx"
If Dir(fichier) <> "" Then Set wb = Workbooks.Open(fichier)
   
      Application.ScreenUpdating = False
    
            For Each Ws In ActiveWorkbook.Worksheets 'on vérifie si une feuille porte le nom de la machine sélectionnée
                If Ws.Name = cb1 Then
                
                Range("A:A").EntireColumn.Hidden = False
                
                Dim x As Range
                Set x = Sheets(cb1).Range("A:A").Find("11", , xlValues, xlWhole, , , False)
                If Not x Is Nothing Then
                    Former.ChkB11 = True
                Else
                    Former.ChkB11 = False
                End If
                                    
                Else 'si aucune feuille, on sort
                    Range("A:A").EntireColumn.Hidden = True
                    Workbooks(cb3).Close
                    Exit Sub
        
                End If
            Exit For
            Next

        Range("A:A").EntireColumn.Hidden = True
        Workbooks(cb3).Saved = True
        Workbooks(cb3).Close

End Sub