I tried Windows Update to install updates (199 of them). It got stuck on 164 of 199. After aborting process, I used a restore point to restore the system to the point before the updates were installed. After that happened, I had 172 GB remaining (before even touching Windows Update in the first place, I had 178). Is there anyway that I can regain all the disk space I had left before because some of it is still lost even after the restore point was used (Windows Update took excess amounts of disk space and put excess amounts of fragments into the hard drive, causing the machine to run slow)?