I am getting this message while opening a file in MS Excel 2010. Can anyone please tell me about this and how to open this file ?

It means that the file has become damaged and can no longer be opened, restore it from your backup.

You might try to download OpenOffice and see if it will open it. That worked for me a few years ago.
OpenOffice is a free alternative to Microsoft Office. Download and install it, but don't let it become the default application for spreadsheets (you will probably want to continue to use the Microsoft programs).

Open Calc (the Excel equivalent) and then find your corrupt spreadsheet. If it opens, save it with a different name, using the .xls or .xlsx format.

Good luck,
WallyH

This can also happen if the file was not made by you and has non recognizable characters in the name. In that case just rename the file.