[dba-Tech] Retrieving Deleted Files off a hard drive

Everyone,

I recently had a discussion with a coworker about the subject of retrieving deleted files off a hard drive.  We got on the subject because we are having an audit on those company-owned computers systems that some staff may have at home for business use.  He claims that any file can be reclaimed, even if a defragmentation has been run.  I thought that once a disk has been defragmented, those files were truly gone, if the anyone defragmented the disk, the audit would basically be a waste of time.  Is this true?  The computer security group here is, I'm sure, quite good, don't let any limitations be considered in any advise returned to settle this score.  

If it is possible, does that also apply to a reformatted disk?  I would think that a reformatted disk would be the ultimate cleanup, but that would have me wondering now if a defragment doesn't work.  Which would cause some serious concerns at this location as much of the stuff that I work with is very sensitive and would make me wonder about correct processes when buying a new machine and excessing the old one.

Thanks for your help in settling the discussion.


Ken Stoker
Technology Commercialization
Information Systems Administrator
PH: (509) 375-3758
FAX: (509) 375-6731
E-mail:  Kenneth.Stoker at pnl.gov