View Full Version : External HD unmounting

4th October 2015, 08:15 PM
I have a few external HD's. All work ok except one, a WD MY Passport Ultra 2 TB. When I connect it to my iMac is mounts but shortly, with in a minute dismounts. When I connect to my Mac Book it works perfectly. I did a diagnostic on the mac book and no issues. I even reformatted it just in case, and when I reconnect to the iMac still does the same thing, mounts and then dismounts.



Andrew T Chadwick
5th October 2015, 09:04 AM
Is the WD Passport drive connected directly to the iMac or is it connected to a USB hub? If it is connected to a USB hub it might not be getting enough power to run the drive. Connecting directly to the iMac should work .

6th October 2015, 12:30 AM
I have connected both ways, and same thing happens either way. Mounts for a few seconds then disappears, but only on the on the iMac. I had it connected to my Mac Book and did a back up that took several hours and no problem.


13th October 2015, 09:59 PM
I sent an inquiry to WD and they suggested all the normal things, 1 connect directly to computer, done, 2 make sure I am using the correct cable, done, see if it shows in Disk Utility, and use verify and disk repair, but there is does same thing. Because it works OK on the Mac Book they are thinking it may be something with the iMac it's self. Any thoughts?