Issue formatting Seagate external in High Sierra

I have been using Seagate external hard drives for years to store data on them, and as an external time machine. I have always formatted them to Mac OS extended in disk utility. Since updating to High Sierra, I can no longer do that. It actually brick's the hard drives, and doesn't let them mount. I get an error message that says "unmounting disk. Mediakit reports not enough space on device for requested operation. Operation failed.

The disk is then greyed out, and says not mounted. The only way I can reactivate it is to do it in Windows through Parallels and then format it there back to Windows NT. This has happened on 2 brand new drives.

I've spoken to Seagate and they say it's a High Sierra issue, and that I have to use Paragon for now. I find this hard to believe.

Does anyone have any help to offer?

Cheers

MacBook Pro with Retina display, High Sierra 10.13.1

Posted on Nov 21, 2017 6:24 AM

Top-ranking reply

blacksun

Level 1

9 points

Posted on Jan 5, 2018 9:53 AM

Here's what I did:

1. I disconnected the power to my unmounted (grayed out) 4T Seagate Backup Plus Hub drive.

2. Then I powered up the 4T Seagate drive. Dialog box popped which said that the drive could not be read, I clicked "Initialize..." and this loaded Disk Utility.

3. Under "View" in Disk Utility, select "Show All Devices"

4. The Seagate physical drive was shown with my previous attempts at partitioning grayed out below.

5. I clicked on the physical drive (NOT the drive partitions below!) and selected "Erase" (NOT "Partition"!) from the tabs above.

6. I just allowed Disk Utility to select the drive format type as you did and clicked OK. The drive was formatted as you would expect (finally).

7. I then selected the drive and used "Partition" to set up the drive to use APFS.

You were my inspiration though! Thanks!

View in context

16 replies

Jan 19, 2018 1:58 PM in response to jibberj

Actually, the screenshot you sent is exactly the one if you have not activated Show All Devices, but only the Show Only Volumes option in the View Dropdown (there are subtle differences. For example, you wouldn't see Macintosh HD, but the drive denomination, and not the used quantity , but the smart status, etc). So, as I see it, Eau Rouge was the right path form start on.
Has High Sierra introduced as default the view volumes only option? what for, to protect a user form himself who has found its way to disk utility?

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Issue formatting Seagate external in High Sierra