I recently began cleaning out junk programs and files when I noticed that my 500gb hard drive has 89.3 GB free of 451gb. I ran windirstat to see exactly where all my memory went and when It shows me the report it says all the files on the drive only accumulate to 175GB. So my question is where is the rest of my memory? I thought maybe it might have been put in as a back up but it is not. And I checked my partitions and the all match. Where is my missing memory?