Hard Drive Preview / Disk Utility Used Space Discrepancy? So I recently cleared a lot of space off of my hard drive as a sort of "spring cleaning," and I got it down to less than 40GB, but my computer doesn't seem to agree with itself on that. If I look at the info of my hard drive on my desktop, it gives me this: 

but when I look at the partition in Disk Utility, it gives me this: 

How do I get DiskUtil to realize how small my hard drive is?
Do you have Time Machine enabled? This could be a result of the Time Machine snapshots...  

Have you looked at this thread here: How to fix Disk Utility, About This Mac, and Finder that disagree on hard drive space usage?

To disable Time Machine Snapshots : 

Open the Terminal from Applications/Utilities
Enter : sudo tmutil disablelocal
Enter your password at the prompt