' Deklarieren der nötigen API-Routinen:
 
Private Declare Function SendMessage Lib "user32" Alias "SendMessageA" (ByVal _
  hwnd As Long, ByVal wMsg As Long, _
        ByVal wParam As Long, ByVal lParam As Long) As Long
 
Private Declare Function FindWindow Lib "user32" Alias _
        "FindWindowA" (ByVal lpClassName As String, _
        ByVal lpWindowName As Long) As Long
 
'DetectExcel() zum Suchen nach geöffneter Excel-Anwendung
Sub DetectExcel(hwnd As Long)
 
    Const WM_USER = 1024
    'Dim hwnd As Long
    hwnd = FindWindow("XLMAIN", 0)
    If hwnd <> 0 Then    ' 0 bedeutet, daß Excel nicht ausgeführt wird.
        SendMessage hwnd, WM_USER + 18, 0, 0
    End If
 
End Sub

Dim XL1 As Object
 
Call DetectExcel(hwnd)
 
    If hwnd <> 0 Then
        Set XL1 = GetObject(, "Excel.Application")
    Else
        Set XL1 = CreateObject("Word.Application")        
    End if