How to release Interop COM excel object by C#

Hi

  I have developed winform application to get details of excel application which currently  running in user machine.Using "AccessibleObjectFromWindow" I have reterived current excel file details and applied to new Excel.Application object .After completing functionality I have did object releasing using 

Marsharl.ReleaseComObject(Excel.worksheet),

Marsharl.ReleaseComObject(Excel.Workbook),

Marsharl.ReleaseComObject(Excel.application)

Issue:

But I am facing issue here like object is not released even if the physical file is closed.

I have tried  Excel.workbook.close() approach, but its closed the physical file itself before user close the file.

Kindly guide me how to  release Excel.Application,Excel.Workbook,Excel.Worksheet object    , dispatch from original resource of file.

Thanks ,

Meenakshi k