EHD capacity and availability discrepancy

I have a WD My Book 4TB EHD that I connect to my iMac 5 via Firewire 800, running OSX 10.8.5. The ‘Get Info’ on the EHD tells me that I have used 2.93TB, with 1.07TB available to use. However, I know for certain that the total of all the files and folders that are visible within the EHD add up to a total of 1.2TB (have added them up correctly three times). Therefore logic says that I should have 2.8TB available to use, not 1.07TB.

As far as I’m aware I haven’t knowingly partitioned the disk, and I have (again as far as I’m aware) emptied the EHD trash. So why the discrepancy? Am I missing something? Will I just have to reformat? I’d rather not as it means copying the current content and then re-copying back once formatted, this will take hours out of my life!! Please help…

Welcome to the Community.

It could be a display error or more files are stored into the drive. Connecting the drive to another computer and comparing the used space would provide a second opinion. If the used space matches then checking if Time Machine is storing data into the drive would be the next step.


Thank you for the reply. Connected to another iMac, same used space. So how do I check if Time Machine is storing data into the drive?

 Just used Disk Inventory X to find out what’s going on, and even that is telling me that 2.7TB is used up yet it’s own evidence would suggest otherwise (I’ve totted up the total capacity used in the window on the right and it comes to just over 1.1TB). Go figure!!