FROM A WEBSITE ON SFC:
To protect your computer from old system files, Microsoft created a special service that is built into the operating system. This service monitors your system files, and if one is replaced or deleted, ICS will automatically restore the system file.
SFC works in conjunction with a utility called Windows File Protection that keeps the system file cache: (%Systemroot%\System32\Dllcache) uppdated with the newest Microsoft Approved files as they are installed on your system. I prefer to use the system backup for the ability to roll back to a former configuration however.
To manually invoke the system file checker, be sure you have administrative access then go to the command prompt and type:
sfc /scannow
The system will immediately begin to check all the current system files and restore the cached approved copies. You may be asked to insert the Windows CD as well during the restore.
IS THERE ANY SOFTWARE AVAILABLE TO DOWNLOAD SO THAT I DONT’T HAVE TO USE THE CD?