To open an excel file  in Visual studio use the following

Dim xlApp As New Excel.Application
        Dim xlBook As Excel.Workbook



        xlBook = xlApp.Workbooks.Open(path to the file)
        xlApp.Visible = True

Job done nice and simple  excel opens the file and closes the process when you close excel.

If you do GC.collect at the end it will do a garbage collection.