Yesterday I’d just completed a painful migration from an old Macbook Air to my new Macbook Pro. I went old-school manual due to the amount of cruft Migration Assistant had loaded the last time I used it; I guess after 10 years it was time to start fresh.
For one of my final tests, I launched VMWare Fusion (version 8.5.1) on my new Mac. It prompted me to enter my password, so it could “adjust some settings”. Which I did. Big mistake.
After about an hour of a spinning beachball, I force-rebooted the Mac. When I logged in, I got a dialog box saying my Library folder had to be repaired, with a Cancel and a Repair button. Clicking either of these immediately showed the same dialog again.
Based on this thread, it looks like there’s a really nasty bug in Fusion, where on Mac OS X 10.12.5 it somehow (by following a symlink?) changes the owner of everything on your Mac to root. That includes your user’s home directory. which makes the Mac unusable. I know the thread implies this is a very unlikely situation which also required a corrupted disk or some other problem, but I think that’s a bunch of hooey.
I wasn’t about to start over, so after several false starts, I wound up following this procedure:
- Boot the Mac in “single user mode“, by holding down cmd-S during startup. I had to select an account to use, but I didn’t enter a password – seems odd.
- This boots to a terminal UI, and after a few minutes the various startup messages ended. The fun part is that it’s using full resolution for the display. We’re talking 3 point text on my Macbook Pro. I’ve never felt so old, as I pretty much had to take off my glasses and press my nose against the screen to read anything.
- The terminal displays some helpful hints about what commands to run next.
- The first one is
/sbin/fsck -fy, which checks your disk for corruption issues. That command was fine, and completed without issues.
- The second one is
/sbin/mount -uw /. Unfortunately on Mac OS Sierra you have to provide a filesystem type parameter (-t fstype). I tried
-t hfs, but that no longer works. After a fair amount of searching I found that Sierra uses the Apple File System, which I guessed was type “apfs”. Running
/sbin/mount -t apfs -uw /worked, and my disk was now mounted.
- The first one is
- At this point I could list my home directory files via
ls -l /Users/kenkrugler/, and I saw that they all had their owner/group set to
root:wheel, which was wrong.
- I tried to fix them up via
chown -R kenkrugler:staff /Users/kenkrugler, but this failed with an error about “kenkrugler” not being a valid user.
- This question on Super User explained that Mac OS X uses Directory Service, not the
/etc/passwdfile for keeping track of users. But when you’re booted in single user mode the Directory Service isn’t running. Luckily I found a folder that hadn’t been converted, which showed me the user as “501”, which is the raw id.
chown -R 501:staff /Users/kenkrugler/took a while, and reported a number of issues with files that couldn’t be changed, but in general seemed to work.
exitreturned me to a regular boot of my user, which worked.
So now I’m back in business, after only a few hours of pain and suffering.