Prüfen, ob Programm schon disposed wurde

    'Um Instanz am ende "abzuschießen",  
    'da das Quit/Close nicht korrekt arbeitet  
    Public Property procProcessesBeforeStart As Diagnostics.Process()
    Public Property procProcessesAfterStart As Diagnostics.Process()
    Public Property procProcessId4Excel As Int64 = -1  'Um Instanz am ende "abzuschießen"  
	
    ''' <summary>  
    ''' Gibt die ProcessID der aktiven gerade erstellten Excel Instanz zurück  
    ''' </summary>  
    ''' <returns></returns>  
    Public Function GetExcelProcessID() As Int64

        Dim _intID As Int64 = -1
        procProcessId4Excel = -1
        For Each _itemAfter As Process In procProcessesAfterStart
            Dim _bolDrin As Boolean = False
            For Each _itemBefore As Process In procProcessesBeforeStart
                If _itemBefore.Id = _itemAfter.Id Then
                    _bolDrin = True
                Else
                    _bolDrin = False
                End If
            Next
            If _bolDrin Then
                Continue For
            Else
                _intID = _itemAfter.Id
                Exit For
            End If
        Next
        Return _intID
    End Function


    ''' <summary>  
    ''' Killt diese Instanz von Excel endgültig aus dem Speicher  
    ''' </summary>  
    Public Sub KillExcelThisInstanz(Optional _bolShowError As Boolean = False)
        Try
            If procProcessId4Excel >= 0 Then
                Dim _procExcel As Process = Process.GetProcessById(procProcessId4Excel)
                _procExcel.Kill()
            End If
        Catch ex As Exception
            'hier Fehlerhandling  
        End Try
    End Sub
	
    Public Sub Beispiel()
	    procProcessesBeforeStart = Diagnostics.Process.GetProcessesByName("Excel") '<---- !!   
            Dim objXLApp As New Microsoft.Office.Interop.Excel.Application
            Dim objXLSheet As Microsoft.Office.Interop.Excel.Worksheet
            Dim objXLRange As Microsoft.Office.Interop.Excel.Range
            procProcessesAfterStart = Diagnostics.Process.GetProcessesByName("Excel") '<----- !!  
            procProcessId4Excel = GetExcelProcessID()  '<--- ProzessID der aktuellen Instanz  
            objXLApp.Workbooks.Add("xxxxxxxx")  
            objXLApp.Visible = False
            objXLApp.WindowState = Microsoft.Office.Interop.Excel.XlWindowState.xlNormal
            objXLSheet = objXLApp.Workbooks(1).Sheets(1)
            objXLRange = objXLSheet.Range("C2")  
            objXLRange.Value = "blahblah"  
            If IO.File.Exists("xxxxxxx") Then IO.File.Delete("xxxxxxx")  
            objXLApp.Workbooks(1).SaveAs("xxxxxxxxxx", Microsoft.Office.Interop.Excel.XlFileFormat.xlWorkbookDefault)  
            objXLApp.Quit()
            KillExcelThisInstanz()  '<---- und heier wird diese Instanz wider gekillt  
	end sub