Private Sub Workbook_Open()
  Dim Eintrag As CommandBarControl
  
  For Each Eintrag In Application.CommandBars("Worksheet Menu Bar").Controls(6).Controls
    If Eintrag.Caption = "E&xprt..." Then
      MsgBox "Exprt already loaded. (Use 'Exprt...' on the 'Tools'-menu)", vbExclamation, "Excel Password Removing Tool"
      Exit Sub
    End If
  Next Eintrag
  Set Eintrag = Application.CommandBars("Worksheet Menu Bar").Controls(6).Controls.Add(Type:=msoControlButton, temporary:=True)
  With Eintrag
    .Caption = "E&xprt..."
    .OnAction = "mainexprt"
  End With
  MsgBox "Exprt now loaded. (Use 'Exprt...' on the 'Tools'-menu)", vbInformation, "Excel Password Removing Tool"
End Sub

Private Sub Workbook_AddinUninstall()
  Dim Eintrag As CommandBarControl
  
  For Each Eintrag In Application.CommandBars("Worksheet Menu Bar").Controls(6).Controls
    If Eintrag.Caption = "E&xprt..." Then
      Eintrag.Delete
    End If
  Next Eintrag
End Sub