Sub Auto_Open()
Dim mi As Object
Dim mb As Object
    On Error Resume Next
    Call Auto_Close
    For Each mb In MenuBars
        With mb.Menus("Tools")
            Call .MenuItems.Add("Unprotect sheet", "UnprotectSheet")
            Call .MenuItems.Add("Unprotect workbook", "UnprotectWorkBook")
        End With
    Next
End Sub

Sub Auto_Close()
Dim mi As Object
Dim mb As Object
    On Error Resume Next
    For Each mb In MenuBars
        For Each mi In mb.Menus("Tools").MenuItems
            If mi.Caption = "Unprotect workbook" Or mi.Caption = "Unprotect sheet" Then
                mi.Delete
            End If
        Next
    Next
End Sub

Sub AutoClose()
If Workbooks.Count >  1  Then
    Call CreateMyButtons 'создает кнопки
End If
If Workbooks.Count =  1  Then
    Call DeleteMyButtons 'удаляет кнопки
End If
End Sub

If Workbooks.Count >  1  Then
    Call CreateMyButtons ' в начале кода идет Call  DeleteMyButtons
End If
If Workbooks.Count =  1  Then
    Call DeleteMyButtons
End If