Recovering Data on Hard Disk

You cannot "access" them? Is that the error that you are getting?

If yes, then it sounds as if someone changed the permissions on those files/folders. If you are an administrator of the local machine, then log on as Admin and Take Ownership back. Otherwise, speak with your Network Administrator.

If no, and you are actually getting clicking/clacking sounds and the computer hangs when trying to access those files/folders, then you might have a failing hard disk drive on you hands. Backup the system immediately, and go from there (either take it in to a repair shop, or replace the hdd, and copy the data files back to the new hdd).