1 MacBook Won't Mount External Drives After New Sierra Install
MacBook Pro mid-2012 15"
I just upgraded my 1Tb SSHD to a 2Tb SSHD. Trying to clone the drive never worked (that's a different story), so I did a clean install of macOS Sierra. I was running El Capitan before.
I put the old 1Tb SSHD in an external USB case and plugged it in. The light on the external case blinks frantically... for days, but the drive never mounts and is not visible in Disk Utility. I can unplug it and plug it into a Linux box which mounts it immediately.
I thought I'd just copy from the old drive to a USB thumb drive on the Linux box. I can copy files to the thumb drive, but when I insert the thumb drive into the MacBook... nothing. It has no light to blink, so I don't know if the MacBook is trying to read it, but I've tried removing and reinserting several times with the same result. Also not visible in Disk Utility. Back to the Linux box, where it mounts instantly.
Both the USB thumb drive and the external case worked fine under El Capitan on this same machine.
Any ideas?
Is this a good question?
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Got the thumb drive to work by shutting down the computer then restarting it.
It still won't mount the external USB SSHD, and disk utility freezes with a spinner, "Loading disks."
Oh, well. back to copying over Ethernet from the Linux box.
by G Hu
Still broken; today I inserted an SD card into the built-in slot, and *IT* won't mount either. Same story: mounts instantly on a Linux box.
by G Hu
Is the the Retina model or a standard model?
by mayer
Retina.
I did finally get it to recognize the SD card by quickly and briskly inserting and removing it repeatedly, thinking it might be dirty contacts. (I know that's not a good way to clean the contacts, but it worked). That could also be the problem with the USB port, but having both go at once, and the timing... Right after a major software update.
I will try a more thorough (and proper) clean of both and see what happens.
by G Hu