'------------------------------------------------------------------------------------------------
' Добавление меню при установке add-in (работает нормально) :
Private Sub Workbook_AddinInstall()
  Call AddDIGIMenu
End Sub

' Удаление меню при установке add-in (работает нормально) :
Private Sub Workbook_AddinUninstall()
  Call RemoveDIGIMenu
End Sub

Private Sub AddDIGIMenu()
     Dim cbmCommandBarMenu        As CommandBar
     Dim cbmDemoMenu              As CommandBarPopup
     Dim cbmCommandBarMenuCascade As CommandBarPopup

    ' Clear the way for new menu.
    On Error Resume Next
        Application.CommandBars("Worksheet Menu Bar").Controls("&DIGI Converter").Delete
    ' Identify built-in menu bar to work with.
    Set cbmCommandBarMenu = Application.CommandBars("Worksheet Menu Bar")
    ' Add the new menu.
    With cbmCommandBarMenu.Controls
       Set cbmDemoMenu = .Add(Type:=msoControlPopup, Before:= 3 )
       ' Set caption for new menu.
       With cbmDemoMenu
          .Caption = "&DIGI Converter"
          ' Add single menu item and set properties.
          With .Controls.Add(msoControlButton)
                        .OnAction = "DigiConvert"
                        .Caption = "&Convert active sheet"
                        .Tag = "DigiConv"
           End With
        End With

     End With
End Sub

Private Sub RemoveDIGIMenu()
    On Error Resume Next
        Application.CommandBars("Worksheet Menu Bar").Controls("&DIGI Converter").Delete
End Sub

Public Sub DigiConvert()
' Здесь код  конвертера, опущен за ненадобностью 
End Sub

'------------------------------------------------------------------------------------------------