If the Windows registry is corrupted due to a virus attack or due to some changes made on Windows, it might cause opening files as the file associations might not be correctly matched. If you find that you are unable to open any particular files in Windows 7 or Vista, you can now try to fix the file association with File Association Fixer. All you need to do is to identify the type of file and use File Association Fixer.
File Association Fixer detects whether you have Windows 7 or Windows Vista installed and accordingly offers you the relevant fixes only. To fix the association for a particular file type simply click on the file type association icon or name. You may have to reboot your PC after you have fixed the associations.
Currently the app offers 18 fixes for Windows 7 and 26 fixes for Windows Vista.