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External Hard Drive

Why does my external hard drive show up in USB device tree but not in Disk Utility or Finder?


My WD My Book that has my Time Machine back-ups will no longer show up in Disk Utility or Finder, but I still it listed, with info, on my USB Device Tree. Any thoughts on what to do to fix it?


This is an iMac (21.5-inch, Mid 2010) running High Sierra

iMac 21.5″, macOS 10.13

Posted on Jun 23, 2021 8:49 PM

Reply
Question marked as Top-ranking reply

Posted on Jun 23, 2021 9:21 PM

Hello, emensi.


NOTE–Consider making a fresh backup or clone of your Mac on a separate drive before attempting Disk Utility First Aid on your TM drive.


If you can't see the external drive in Finder or Disk Utility, reboot the computer and see if that changes things.

Shut down, unplug your connected devices and restart the computer. Then reconnect the external drive and see where things stand.


If that doesn't fix the issue, please see if the problem still happens in Safe mode.

How to use safe mode on your Mac - Apple Support 


Does the problem persist while in Safe mode? If not, then leave safe mode by restarting your Mac normally and re-evaluate the issue again after a normal reboot


Change the drive connecting cable. Does that fix the problem?


If you can get Disk Utility to recognize the drive, then you can run First Aid on the volume and the device.

How to repair a Mac disk with Disk Utility - Apple Support: https://support.apple.com/en-us/HT210898

1 reply
Question marked as Top-ranking reply

Jun 23, 2021 9:21 PM in response to emensi

Hello, emensi.


NOTE–Consider making a fresh backup or clone of your Mac on a separate drive before attempting Disk Utility First Aid on your TM drive.


If you can't see the external drive in Finder or Disk Utility, reboot the computer and see if that changes things.

Shut down, unplug your connected devices and restart the computer. Then reconnect the external drive and see where things stand.


If that doesn't fix the issue, please see if the problem still happens in Safe mode.

How to use safe mode on your Mac - Apple Support 


Does the problem persist while in Safe mode? If not, then leave safe mode by restarting your Mac normally and re-evaluate the issue again after a normal reboot


Change the drive connecting cable. Does that fix the problem?


If you can get Disk Utility to recognize the drive, then you can run First Aid on the volume and the device.

How to repair a Mac disk with Disk Utility - Apple Support: https://support.apple.com/en-us/HT210898

External Hard Drive

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