Recovering data on windows 10 help needed please

[ArcticFrenzy]

hello there, as the title says i have a friend who upgraded to windows 10 from windows 7 and for some reason it wipped his HDD, now ive been told that its possible to recover this data (there is no windows old file) but i was wondering what tool he should use, also hes a student so money is pretty tight.

thanks for the help in advance

 

[KraniX]

Tech Radar have an article on some of the best free options.

http://www.techradar.com/news/software/applications/best-free-data-recovery-tools-1321723