Free space disappeared to 12GB from 120GB on C drive

[ozwashere]

I can't find out where my free space on drive C disappeared (windows files are on C drive). The disappearence of C drive disk space happened slowly but steadily and stopped at 12GB. I tried using WinDirStat program for accurate C drive size. The program says that I used up only 50GB of space out of 120GB but on "my computer" it says that I only have 12GB of free space on C drive. I have a few other drives "D:" , "E:" , and it seems like there's no problem with them at all. I tried running disk check up, virus scans. Nothing seems to make any effect. I'm using windows 8. Would anyone suggest some other solutions on how to atleast know what uses my free disk space and possible how I could get it back?

 

[patrickIT]

Could you run this program ---> windows key + r ---> psr.exe
And post output in this thread .

And run this program link below;
http://www.uderzo.it/main_products/space_sniffer/download.html

 

[ozwashere]

I ran all the other programs as an admin with full rights, but apparently only space_sniffer actually showed me what takes up my space. Thank you.