Dim xlApp As Excel.Application = New Excel.Application
        Dim xlwbBook As Excel.Workbook
        xlwbBook = xlApp.Workbooks.Open("C:\temp\excel.xls")
        System.Threading.Thread.Sleep(1000)
        xlApp.Quit()
        xlApp = Nothing
        xlwbBook = Nothing
        GC.Collect()
        GC.WaitForPendingFinalizers()
        GC.Collect()
        GC.WaitForPendingFinalizers()