Quote Originally Posted by benagain
When you delete something it flags it as deleted so when you check my computer you see you have X ammount of disk space left (even though the data is still there). It'll stay there till you save something in that space. Once you do, it's gone for good.
Ah. See, I knew about how data just lies around still there, but I thought somehow it could be recovered even after having been written over, and I was wondering how the hell that's possible.
Quote Originally Posted by Big Calhoun
Since you reformatted the computer, you're going to need a heavy duty app to recover that data. More than likely, reformatting also overwrote your FAT table, this is where your OS keeps track of where files are/were. If that is overwritten, then a typical undelete app has no 'starting point' to recover the information. You'll need something a little more heavy duty that'll be able to analyze the raw contents of the file.

Get a CD burner and always back things up!!
Yeah, but that's only for FAT filesystems, right? For example, I use ReiserFS which uses a completely different algorithm to keep track of all the files/directories.