Help! I have an external 1TB drive. I click "Get Info" on the drive and it says that 983GB of 1TB is used. However, when I click "Get Info" on the two subfolders in the drive, one says "600GB used" and the other says "30 GB" used. Where is my other 370 GB? I've emptied the trash and used disk utility to write zeros on free space. Also restarted. Any ideas?