I have a 2012 MacBook Pro 15" Retina, running MacOS Sierra version 10.12.3 (16D32). I have a 1TB WD "My Passport Ultra" external HDD that I've been using exclusively for Time Machine backups for a year or so. Today, 11 days since my last backup the following happens:
- I plug it in and forget about it while browsing the web.
- Notice Time Machine isn't backing up, so click "Back Up Now".
- Get notification toast in MacOS from Time Machine: "Backup Disk Not Available: Try backing up again when "My Passport" is available."
- Open Finder, notice disk does now show up under "Devices" in sidebar.
- Open Disk Utility, no disks show up, just says "Loading Disks..." for ever.
- Close Disk Utility, unplug external HDD, re-open Disk Utility.
- Internal disk appears.
- Plug in external HDD.
- Shows up after a bit of a delay.
Things I've tried:
- Turning off and on again (reboot as well as shutdown etc).
- Disk Utility's "First Aid" option - which says there are no problems.
Other point to note:
- I had HDD plugged-in, opened Disk Utility, which hung (as expected from point 5 above) then I just pulled the USB cable and immediately, Disk Utility finished loading disks and showed the internal HDD. Plugged external back in and after a short delay it shows up in Disk Utility.
- I notice it does show up under the USB 3.0 section of System Information.
I'm a Windows guy historically, so any advice, even seemingly obvious advice, would be appreciated.