I have a WD My Book 4TB external hard disk running on an iMac running OSX 10.8.5. The 'Get info' says I've used 2.93Tb of the EHD yet I've totted up all my folders and they only take up 1.17TB space. As far as I'm aware I haven't partitioned the disk (even accidentally if that were possible!), and also as far as I'm aware the trash for the EHD is empty. So what's using up the space, and am I going to have to reformat to get it back? Please help...