External Hard Drive not Mounting

Since updating to macOS Sierra, my Seagate 1TB Harddrive isn't being read or mounted by my Retina MacBook Pro (2014) ... It appears in Disk Utility but not in Finder or on the Desktop ... In Disk Utility I cannot do anything but format it which I DO NOT want to do .. Any suggestions or help?!

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I really hope you find an answer to this. I'm having the same issue. My entire iTunes library is on the portable drive...

I just downgraded to El Capitan, I couldn't handle it, it was too much for me :/ So I wish you all the best! If I do come across some method I'll be sure to pass it through here to you though 🙂

Similar issue with my Western Digital external USB drives. None mount, but they are also not seen by Disk Utility. They do show up in the System Information utility as being seen on the USB bus, but don't show as HDs.

Me too with WD external usb passport 0730. Is detected in report system but not mount !. May be is necessary any way to restart scan usb?

I have this issue too with any external hard drive, they do not show up in the Disk Utility. This issue, is not a Seagate-specific issue.

Same here, all drives appear on the bus in the system, but only the seagate mounts. Terrible part, the missing drives are my Time Machine and Downloads. Ugh. So literally, I cant update my apps, use iTunes, backup my machine, etc. I'm thinking about rolling out of the beta.

Exactly the same thing for me. My Time Machine is on one and my downloads on the other. WD Passport drives.

Mine is limited to USB HDs. I have two Thunderbolt drives (Drobo 5D and a G-Drive) and they mount fine. No USB HDs mount. USB flash drives (sticks and camera cards) mount without problem.

None of the HD I would like to connect to this Mac have a Thunderbolt connection but that is helpful if the hard drive you would like to connect have that connector.

Yes, USB Sticks seem to work fine, I had a crash from connecting one stick and the Mac rebooted but they mount.

same here, none of my USB external drives are connecting or visible anywhere. i guess we have to wait until the next beta

Same here with WD My Book

I have a 1TB Seagate (FAT32) and 4TB Seagate (Mac OS Extended), and the 1TB works perfectly fine under USB while my 4TB just shows up in disk utility

I have 2 external drives that do not mount.

And my apple usb wired keyboard doesnt work either.

MacBook Pro (Retina, 15-inch, Mid 2015)

My WD external hard drive will not mount and does not show up anywhere. I also can't go back to an older OS because my backup is on my external HD. All my files are on external HD so iTunes is useless and everything else. I hope they fix this soon.

My WD My Passport USB3 drive is not appearing but my Transcend SSD on USB 3 is being seen.