'Prozessliste, bevor ich einen Excel-Prozess starte
process1 = Process.GetProcesses()
oExcel = CreateObject("Excel.Application")
'Prozessliste, nachdem ich einen Excel-Prozess gestartet hab
process2 = Process.GetProcesses()

Dim process1() As Process
Dim process2() As Process
Dim procId As Integer = 0

        Try
         ...
        Catch
        Finally
 
            Dim bMonProcessXL As Boolean
 
            For j As Integer = 0 To process2.GetUpperBound(0)
                If process2(j).ProcessName = "EXCEL" Then
                    bMonProcessXL = True
                    For i As Integer = 0 To process1.GetUpperBound(0)
                        If process1(i).ProcessName = "EXCEL" Then
                            If process2(j).Id = process1(i).Id Then
                                bMonProcessXL = False
                                Exit For
                            End If
                        End If
                    Next i
 
                    If bMonProcessXL = True Then
                        'Jetzt, wo ich die genaue ID habe, kann ich sie töten. 
                        ' excellAppl.Hinstance  
                        'funktioniert nicht mit Excel 2000, während diese 
                        ' Methode immer geht!
                        procId = process2(j).Id
                        Process.GetProcessById(procId).Kill()
                        Exit For
                    End If
                End If
            Next j
            End
        End Try