Hmmm, everthing you delete or even delete from the recylcle bin (emptying the recycle bin) is still technically on the harddrive, they are just invisable. Its not until you use up the addresses by installing more software etc that it overwrites what used to be there. For example it is possible to Format your drive then get it back again using certain recovery programs. I have recovered an accidentally formatted drive before so I do know it can be done. The program you are talking about probably has the ability to see the deleted things even tho they dont show up when you do a search. Hope I have explained this clear enough.
