Option Explicit
 
Dim xlAppl As Excel.Application
Dim xlApplLiefNicht As Boolean
Dim wb As Excel.Workbook
 
Private Sub Form_Load()
    On Error Resume Next
    Set xlAppl = GetObject(, "Excel.Application.8")
    If Err.Number <> 0 Then xlApplLiefNicht = True
    Err.Clear   ' Err-Objekt im Fehlerfall löschen
    If Not xlApplLiefNicht Then
        If xlAppl.Workbooks.Count > 0 Then
            For Each wb In xlAppl.Workbooks
                MsgBox wb.Name
            Next
        End If
    Else
        MsgBox "Excel läuft nicht!"
    End If
End Sub