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msim20 Author

Level 1

49 points

High Sierra install fails - "unable to unmount volume for repair"

Have a 2012 Mac Mini.

Running Sierra.

Third party SSD running Sierra for more than a year.

Sierra was installed over the previous version of OS.

When trying to install High Sierra, system takes me to a screen that says "unable to unmount volume for repair". Asks me to restart and back to normal login.

Checked the primary HDD via Disk Utility. Everything appears to be ok.

Searched the discussion forum and internet. No solution found.

Any ideas?

Thank you.

Posted on Sep 26, 2017 10:58 AM

126 replies

Oct 9, 2017 7:55 PM in response to msim20

Mac mini (Late 2014)

Same problem. Disk utility reports that all volumes are fine.

Oct 10, 2017 9:40 AM in response to kluetin

Nope - not related to Mac Mini.

I can't upgrade my MackBook Pro (Mid 2014).

Oct 10, 2017 10:01 AM in response to kluetin

For what it's worth, I'm also running Server software on my Mac mini. I believe it's Server 5.3.1. My specs are:

Mac mini (mid 2010)

macOS Sierra (10.12.6)

Server (5.3.1)

500 GB SDD

16 GB RAM

FileVault2

Joe

Oct 13, 2017 11:37 AM in response to msim20

Seeing the same thing on a Mac Mini.

Oct 13, 2017 11:43 AM in response to Brian Papa

Have you removed all external drives then restart?

saint111

Level 1

8 points

Oct 13, 2017 12:37 PM in response to dianeoforegon

I have been having the same issue with my Mac Mini. I have tried disconnecting everything from the computer, excluding the monitor, and the problem still persists.

Oct 14, 2017 5:08 AM in response to msim20

Apple support told me they were aware of the problem.

Any word on a repair/fix date?

Oct 20, 2017 3:49 AM in response to AnAnonymousUser

Yup.

That's what I got too.

etinin

Level 1

9 points

Oct 20, 2017 6:29 AM in response to joe.stolid

No wipe. My procedure preserved all my data. It’s exactly the same conversion the installer does. The problem is that it does not force umount

ttaallff

Level 1

12 points

Oct 21, 2017 10:08 AM in response to iX901

Yes, I tried with both versions. The changed time you mention belongs probably only to the web content and not to the installer (Version is 13.0.66, created 2-Oct-2017 20:59).