In C:\, I select all directories including all hidden files, right click and get 64.8GB disk space requirement but if I right click C:\, it shows that there are 79GB. What could take up so much space? Where is it and how can I erase them or get more space. I checked in C:\WINDOWS\Temp and there were only a few files that took KBs. In CCleaner, I checked everything and analyzed and it will only free 13.5 MB. AVG free edition is not detecting any malware either. I have never installed anything new but I have been playing games and using applications. I hear that IE has really hidden files (http://fuckmicrosoft.com/content/ms-hidden-files.shtml) but I never use IE and I use Firefox always. It says that I can go to true DOS mode and in it I can see really hidden files. So if I am to go to the true DOS mode then I can see what's taking up my space but the problem is I don't know how to get to the true DOS mode. I need help on finding out what's taking up my space and how to free them. Thanks. Another note: some time before, I saw a file in C:\ that has a lot of .TMP files. The folder was taking up GBs of space so I deleted it and freed a lot of space. Now it doesn't show up again.