I'm helping a friend organize their computer and a 2TB External G Drive with a lot of video footage files. In Disk Utility the G Drive reports 1.08TB of data but the folder containing all the files is only around 500GB, almost exactly half that, so there is 500GB of missing space. "About this Mac" reports there is 470GB of "Other" files. I used Disk Inventory X to inspect the contents of the drive. There are no hidden files and nothing equating to anything like that much space in the hidden folders, trashes etc My friend doesn't remember what files she had on the drive so we can't check whether everything is there. Could this be missing/damaged files? How can I find out what this is?