Zoom auto sur toute les feuilles du classeur

Option Explicit
Private Sub Workbook_Open()
Workbook_SheetActivate ActiveSheet
End Sub

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
Columns("A:i").Select
ActiveWindow.Zoom = True
End Sub

Private Sub Workbook_Open()
Dim sh As Worksheet 'déclare la variable sh
Application.ScreenUpdating = False 'masque les changements à l'écran
For Each sh In Sheets 'boucle sur tous les onglets du classeur
    sh.Select 'sélectionne l'onglet
    sh.Columns("A:i").Select
    ActiveWindow.Zoom = True
Next sh 'prochain onglet de la boucle
Sheets("Feuil1").Select 'à àdapter à ton cas
Application.ScreenUpdating = True 'affiche les chamgements à l'écran
End Sub

Option Explicit
Private Sub Workbook_Open()
Workbook_SheetActivate ActiveSheet
End Sub

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
If Sh.Name = "nomfeuille" Then
    Columns("A:N").Select
Else
    Columns("A:i").Select
End If
ActiveWindow.Zoom = True
End Sub

Option Explicit
Private Sub Workbook_Open()
Workbook_SheetActivate ActiveSheet
End Sub

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
If Sh.Name = "nomfeuille" Then
    Columns("A:N").Select
    ElseIf Sh.Name = "nomfeuille2" Then Columns("A:i").Select
    ElseIf Sh.Name = "nomfeuille3" Then Columns("A:P").Select
'etc...
Else
    Columns("A:Z").Select
End If
ActiveWindow.Zoom = True
End Sub