Open Services, find Windows Search, stop it, and change it to manual start.
Then go to c:\Program Data\Microsoft\Search\Data\Applications\Windows and delete the file windows.edb. It will be quite large!
Windows will make a new file after that.
Your problem should be resolved
My C drive is a 500 gig drive, 465 gig of which is usable. Over the last month or two it has been slowly filling up with files that I cannot find or delete. I have viewing of hidden files and protected system files enabled. As of right now if I right click and view properties for drive C it says I am using 442 gig. If I go into the drive c root, select all files and view properties they come out to about 219 gig. Somehow there is over 200 gigs worth of files that I cannot view, even with viewing of hidden files enabled. I have also run WinDIRStat and it came up with the same 219 gig of used space.
I have already run disk clean up, including deleting all but the most recent restore points, and all it did was clear about 10 gig of space.
I run ESET anti virus and firewall. The only thing I can think of is I started noticing this not long after installing Carbonite. Don't know if that has anything to do with it or not, just uninstalled it without effect.