Lot of Mac OS X users reported this issue in Apple support communities. External hard drive showing up in Disk utility not in Devices. This problem also happened after OS X Yosemite update.
Solution 1:-
Go to Settings -> Finder Preferences . Under the General tab, select External drive in “Show these items on the desktop”.

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Solution 2 :-
Go to Disk utility and select the external drive from the left sidebar. Choose verify dis

Wd My Passport For Mac Not Backing Up

c. It will find and correct minor errors.
Solution 3:-
Wd my passport for mac not backing up
If you are connecting your external hard drive with Mac using USB Hub, check the USB hub first.
Passport

Solution 4:-
  1. Open Disk Utility. If your external USB drive drive faded/greyed out and unmountable?
  2. Connect another external drive or Pen drive to computer. This drive also not recognized drive?
  3. Do the proper eject from the Finder window list.
  4. Restart your computer and connect the external drive.
Solution 5:-
  1. From the Finder menu, select “Go to Finder”.
  2. Type the external drive path what appears under Disk Utility. Ex: /Volumes/sleekdisk
Solution 6:-
Drive not showing up in Finder but visible in Disk Utility?
Go to Finder window and view below the favourite list. If the drive greyed Out? Select the drive. It might visible.
Solution 7 :-
Cisco anyconnect for mac
  1. Shut down your Mac computer .
  2. Unplug the power cord.
  3. Unplug all USB connections.
  4. Wait 30 seconds or 5 minutes then plug it back in.
  5. Then turn on your MacBook Pro or iMac.
  6. Plug the external drive only to the USB port. Open Finder and check your drive.
Solution 8:-
Install and run run Onyx (maintenance freeware) or
run Kext_Utility.app.v2.6.1 and restart your Mac machine.
Solution 9:-
Some times this issue might happened because of the unsupported drive format.
Install Fuse for OS X, NTFS-3G for Mac OS X and Fuse wait.
Restart your computer and check the issue.
If the above methods not working?

My Passport Wd Not Connecting

  • Install fresh OSX Yosemite.
  • Connect your segate external drive or WD passport to Windows computer. Delete the partition and connect back to MacBook Pro.

Wd My Passport For Mac Not Showing Up In Finder

If you knew any other solutions, inform us via comment.