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

If your Mac won't boot, there's something else wrong and I can't guarantee the following command will fix your issue. However, with that said, the commands can be executed from recovery mode as well. If your machine's already hosed, I supposed it's worth a try, but I doubt this will fix your problem:

I just remembered after posting, the command may need to be further tweaked for the Recovery Partition. I can check sometime tomorrow on my home machine for you. In the meantime, could anyone else chime in if the below works in the Recovery Partition?

1. Boot into the Recovery partition and click the "Utilities > Terminal" menu item to launch Terminal
2. In the Terminal window, copy paste this command exactly and press the "return" key:

   mv /.quota.ops.user /.quota.ops.user.org

3. We're going to do the same thing again, only this time with a different command. Remember to press the "return" key after pasting it in:

   mv /.quota.user /.quota.user.orig

If after trying this you are still unable to boot, you're going to unfortunately need to reinstall macOS Sierra from the Recovery Partition or from Internet Recovery (this will NOT overwrite your personal data, it will only write over system-level files). Once you can boot normally again you try again by following these steps exactly. Good luck!

Thanks for waiting! To execute the commands from the Recovery Partition, here's what you do:

1. Boot into the Recovery Partition and click the "Utilities > Terminal" menu item to launch Terminal
2. In the Terminal window, copy paste this command and press the "return" key:

   ls /Volumes/

3. A list of partitions will be displayed, one of which is your primary macOS one. By default, it's named "Macintosh HD", but it's possible you renamed it at some point. Note the name if you did rename it and substitute it for "Macintosh \HD" at the points noted below. Otherwise, you can just copy paste the commands as they are! 🙂
4. In the Terminal window, copy paste this command (changing "Macintosh\ HD" if necessary") and press the "return" key. NOTE: If you changed the name at some point earlier and it has spaces in it, you'll need to put '\' before spaces for the command to work. You can try pressing Tab to help you autofill the name, if needed.

   ls /Volumes/Macintosh\ HD/

5. If this command executes successfully you should see "Applications", "Library", "Users", etc. printed. That's good news! That means you've selected the right partition, you're almost there. If not, you may have selected the wrong one, go back to 2. and try another one.
6. In the Terminal window, copy paste this command (again, changing "Macintosh\ HD" to your personally named partition, if necessary), and press the "return" key:

   mv /Volumes/Macintosh\ HD/.quota.ops.user /Volumes/Macintosh\ HD/.quota.ops.user.org

7. And finally, paste this in followed by the "return" key (again, changing "Macintosh\ HD" if necessary):

   mv /Volumes/Macintosh\ HD/.quota.user /Volumes/Macintosh\ HD/.quota.user.orig

As mentioned before, if your machine's not booting normally I doubt this will help, and if it doesn't work you'll have to reinstall macOS Sierra from the Recovery Partition or from Internet Recovery (this will NOT overwrite your personal data, it will only write over system-level files). Once you can boot normally again you try again by following these steps exactly.

It's possible your drive is bad.

• Make a clone backup of your drive.
• Boot from the clone drive.
• Open Disk Utility and select your internal Macintosh HD and erase.
• Run First Aid.

• Install either Sierra or High Sierra on our internal drive. (If you do not have an SSD drive, I suggest you stick with Sierra to install.)
• Bring back your data from clone. I suggest a manual move of data so you don't bring back corrupt files.

Download Sierra

https://support.apple.com/en-us/HT208202

Same problem here.

Tried updating by booting from install stick ... no joy

Took it into Apple - after some diagnostics they determined that there was no problem with the actual drive, but after a few different "levels" of diagnositcs - they finally determined that it was a "software error" (not hardware).

At this point the apple guy was quick to say the only way to fix it - was wipe the drive and go from there, and warned me that if I did a restore from Time Machine - the problem would come back.

Ironically - he wiped the drive after I acknowledged his advice, thinking I gave him consent (he knew I had a fresh backup). When I realized what was going on - I felt sorry for the dude... I had just packed up that morning via Time Machine so I let it slide and restored when I got home.

So I am in the same boat here - unable to update to High Sierra as I am not willing to wipe my drive clean.

Ok. Tried this. An earlier poster pointed out a possible discrepancy in step #2... so I ignored that as it was already mounted.

Here's the results I get from steps #3 & #4...

I should note that I have tried this with all external (Thunderbolt & USB) drives disconnected, apart from the booted external image.

My (much older) 17" MacBookPro (mid-2010) updated with no issues.

Oh, and if it helps, this is a bone-stock 27" 5k iMac as delivered (with internal SSD from Apple).

Well, in my case it's not a Mac Mini, but a 27" iMac.

No modifications. Boot drive is internal SSD as installed by Apple when I ordered the machine.

No funky software that you mention (virus checkers, disk copiers, ugh disk encryption yuk, etc). EtreCheck gives the machine a clean bill of health.

•If any disks/partitions being backed-up are case-sensitive, the backup volume must be, too, so select Mac OS Extended (Case-sensitive, journaled). http://pondini.org/TM/5.html

Personally, I never use case-sensitive.

Rather than use Time Machine > Restore, if you are able to view the Backups.backupdb folder you can drill down to find your data and try dragging it over to your drive.

If you don't have a clone backup it's time to start. Just like a seat belt and an air bag protect you in different ways when driving, you need both Time Machine and a clone for full protection. Restoring from a clone or manually dragging over from a clone is easier IMHO than using Time Machine.

Software used to Clone:

CarbonCopyCloner http://www.bombich.com/download.html (All options are available free for 30 days)

SuperDuper!http://www.shirt-pocket.com/ (Free forever to do an erase and install. Purchased version allows for smart updates and schedules)

Boot into the Recovery Drive to run First Aid from Disk Utility in Recovery.

Boot into the Recovery Drive by holding down Command R when restarting.

Open Disk Utility

Run First Aid on your internal drive, Macintosh HD

Quit Disk Utility

Also check to be sure the firmware is fully updated on your Mini.

About EFI and SMC firmware updates for Intel-based Mac computers - Apple Support

https://support.apple.com/en-us/HT201518

I have same problem

Re: macOS 10.13 could not be installed on your computer , unable to unmount volume for repair

Even the last Installer not solved this issue !

I hope Apple Solve this issue soon

I don't have a MacMini so haven't followed closely but it seems updating the MacMini to High Sierra has been problematic for users. I wonder if this could be a firmware issue.

Check for the Apple Feedback.app in System folder. Normally this app is only a part of the beta but some users have reported it's now an option for non-beta users.

Macintosh HD Root folders

Applications

Library

System/Library/CoreServices/Applications/Feedback Assistant.app

Users

Select Keep in Dock for easy access after launching.

You might consider enrolling in the Public beta. This way you can send detailed reports to Apple to help fix the issue.

Apple Beta Software Program

I suspect it wouldn't let me restore from my Time Machine backup because the backup was made from a different OS --> Sierra. But, that's poppycock, right? Why would it care that I created the backup from a previous OS?!

It doesn't care. You can select to restore files from a previous Time Machine backup of a previous OS. I would choose carefully what you bring over so you can start as clean as possible without bringing in old conflicting files.

How to move your content to a new Mac - Apple Support

How to Clean Install MacOS High Sierra

http://osxdaily.com/2017/10/02/clean-install-macos-high-sierra/

Create a Clone backup

If you don't have a clone backup it's time to start. Just like a seat belt and an air bag protect you in different ways when driving, you need both Time Machine and a clone for full protection. A clone is bootable.

If for some reason you DON'T like the way High Sierra runs, and you want to revert...

1. Boot from the backup clone.

2. Erase the internal drive with High Sierra using Disk Utility and format as HFS+ Mac OS Extended Journaled

3. Clone the backup drive BACK TO the internal drive.

Software used to Clone:

CarbonCopyClonerhttp://www.bombich.com/download.html (All options are available free for 30 days)

SuperDuper!http://www.shirt-pocket.com/ (Free forever to do an erase and install. Purchased version allows for smart updates and schedules)

I suspect the problem with with your version of MacMini. I see reports from MacMini users on other forums. Apple needs to do something to make this work on the older MacMini drives.

Apple doesn’t routinely monitor the discussions. These are mostly user to user discussions. Send Apple feedback:

BugReporter http://bugreporter.apple.com

Free ADC (Apple Developer Connection) account needed for BugReporter. Setup a free account

http://developer.apple.com/programs/register/

Mac OS X Feedback (no account needed)

https://www.apple.com/feedback/macos.html

Contacted AppleCare. These two commands fixed the problem: sudo mv /.quota.ops.user /.quota.ops.user.org and mv /.quota.user /.quota.user.orig

First off, congrats on your first Mac! I'm sorry you're having a bad experience so far with the install process (for what it's worth, High Sierra was the first in install issue I've ever personally had with Macs, they're usually very good with this sort of thing). Here's what you need to do for the install to work:

1. Boot up your Mac normally as if it were any other day
2. Press the "Command ⌘ + Spacebar" keys at the same time to bring up Spotlight. Spotlight looks like a thin, long window where you can do nothing but type, the idea being that at any time no matter where you are or what you're doing on your Mac, you can press these keys, type something, and it will search your entire Mac. Pretty neat!
3. In the Spotlight window, type "Terminal" and press the "return" key
4. You'll see a plain, white window pop up. This window is where you'll enter the commands everyone's been talking about. The program you've just opened is called "Terminal" and is used by developers and "pro-sumers" to do advanced computer tasks using text instead of dragging-and-dropping / clicking things like we normally do with a mouse.
5. In the Terminal window, copy paste this command exactly and press the "return" key:

   sudo mv /.quota.ops.user /.quota.ops.user.org

6. We're going to do the same thing again, only this time with a different command. Remember to press the "return" key after pasting it in:

   mv /.quota.user /.quota.user.orig

7. That's it! You can close the Terminal window and go about the macOS High Sierra install normally, as if you never did any of this at all. Assuming nothing's changed since when I did this, the install should work this time.

Please let me know on this thread if you run into any other issues, I'm happy to help 🙂

Your best option might be to revert to the original OS X that came on your Mac using Internet Recovery. Then you can update to Sierra or High Sierra.

• Internet Recover will re-install the version of OS X that originally came with the Mac.
• Requires macOS Sierra 10.12.4 or later Reinstall the macOS that came with your Mac, or the version closest to it that is still available.

Shut down.

Immediately after hearing the Mac boot chime, hold dhown Shift Opt Cmd R. Keep holding until you see the progress bar. This will boot you into Internet Recovery.

Open Disk Utility. Select Macintosh HD and select Erase. Make sure you have formatted as HFS+

Quit Disk Utility.

Select to reinstall OSX.

Do not select to import any data after installing. You will want to upgrade before bring over any data.