Is it possible to recover a Hard-disk even after formatting and rewriting all space with new data

hard drivehardware

Some coworkers and I are discussing about Hard-disk recovery and one of my coworker said that is possible to recovery a HD even after formatting and rewrite all your space again.

The argument of my coworker is: the magnetic data in disk is never replaced, exist various layers in the disk, even after formatting and all the space rewritten with new data, this new data is written in a new layer.

After formatting a Hard-drive and after rewrite ALL SPACE with new data is possible to recovery the data before formatting?

Best Answer

No that's impossible. In the past the width of the track was not erased entirely with formatting, so after formatting there was still enough magnetic data left to recover the data. Modern days Harddrives have a very narrow width track and especially when data is overwritten again (what is also done with secure erase but then with zero's) the old data is not recoverable. See also: http://en.wikipedia.org/wiki/Disk_formatting