I have 2 x WD My Passport 2TB drives; formatted in exFAT; USB 3 and USB powered. I got them in Dec 2013, so they’re new. I work on a MacBook Pro with OS X Lion.
A couple weeks ago one of my passports suddenly became unresponsive on the MacBook, and couldn’t be unmounted. I tried shutting in the hopes of forcing an unmount , but the Mac just hung, something it has never done before. I attribute that to the external not being unmounted, or unmountable. After a force restart of the Mac, the external would not mount in Finder. It does appear in Disk Utility, but cannot be repaired or seemingly even accessed; all options are greyed out except the option to erase and reformat the entire drive (it only has one partition).
When I tried connecting it to a Windows laptop a warning popped up about possible corruption for not having been correctly unmounted, and suggested I do a scan. I accepted, but the scan itself hung before ever getting anywhere. When I unmounted from Windows and remounted, but declined the scan, the drive was accessible as usual, with no indication of problems. It still would not mount on Mac.
In summary, the drive will not mount on the Mac, but will mount on the Win where it works perfectly after declining an offer to repair because the repair always fails.
I have received a replacement from WD, but today the exact same series of events has happened to my second original drive. Unresponsive drive that cannot unmount and after a forced reboot cannot remount in Mac, but can in Win.
I’ve read a lot about WD issues on Mavericks but I’m still using OS X Lion. Could it be a power thing? The Windows machine is a 2012 VAIO versus a 2011 MacBook Pro.
I find it all rather odd and inconvenient.