Hiya. I have a 2014 MacBook Pro. I also have a 2TB Western Digital MyPassport external HD that's about 12 months old. This HD has no power source, I simply plug it directly into my Mac via the USB port. Recently, my MacBook has only sporadically read my external. I plug it in. The light comes on the HD, it makes the normal "thinking" sound, as if it is being read, but nada on the Mac. Not in Finder, not in Disk Utility. I've ran a couple of terminal commands to check whether it's been marked as "hidden" and it's literally as if there's no HD plugged in. I will leave it for hours and nothing. I don't really have any rhyme or reason for when it does work. Usually once it starts working, it's pretty good for a few goes. I find if I remove the disk without safely ejecting there's little to no chance it will work for a while afterwards. Often, when it finally does boot, it will eject itself quite quickly and come up with the "you have unsafely removed hardware", as if I've pulled the plug, when I haven't touched it. Also, when I reset the entire MacBook, with the HD plugged in, usually my Mac won't boot. It will sit on a black screen, and will only start up once I unplug the external. This makes me think it's not the cord. I'm currently travelling, so don't easily have access to other Mac's to see whether it's my computer or the HD. Anyone ran across anything like this before? Would appreciate any help/advice I can get!