Private myExl As New Excel.Application
 
Private Const sAPPNAME As String = "Pfad_u_Name_der_Excelarbeitsmappe"
 
Private Sub Document_Close()
   Set myExl = Nothing
End Sub
 
Private Sub Document_Open()
    Dim cmdbar As CommandBar
    Dim cmdButton As CommandBarButton
    Dim sXls As String
 
    'Evtl. vorhandene Bar löschen und neu erstellen
    sXls = "Excel"
    For Each cmdbar In Application.CommandBars
       If cmdbar.Name = sXls Then cmdbar.Delete
    Next
    Set cmdbar = Application.CommandBars.Add(Name:=sXls, Temporary:=True)
 
    'Schaltfläche einfügen
    Set cmdButton = cmdbar.Controls.Add(msoControlButton)
    With cmdButton
       .BuiltInFace = True
       .Caption = "Excel Tabelle starten"
       .Style = msoButtonIconAndCaption
       .FaceId = 538
       .OnAction = "Show_Excel"
       .Visible = True
    End With
 
    cmdbar.Visible = True
End Sub
 
Public Sub Show_Excel()
   With myExl
      If .Visible Then Exit Sub
      If .WindowState = xlMinimized Then
           .WindowState = xlMaximized
           Exit Sub
      End If
      .Workbooks.Open sAPPNAME
      .Visible = True
   End With
End Sub