High Sierra install is frozen

Hi, I hope despite it being a few months that this answer will help some of you. I called Apple support and they say they monitor this forum - but no one from Apple has answered in about 3 months so I have my doubts. Anyway I mention that because on the phone the second tier specialist said that this was a good fix and that I should post it.

You should make a copy of the High Sierra installer on a flash drive and use that to install. High Sierra can be downloaded from the App store, but NOT from the update sections on any of the devices. Those aren't full copies. Make sure you've found the full install in the app store and select "download" underneath the icon.

Copy this to a flash drive or external hard drive.

Eject the drive and insert it into your troublesome computer. Disconnect your internet connection. Open the installer, and follow the instructions. Previous to my doing this, the install froze at 1 hour and 21 minutes. Using this method, the install took a total of 21 minutes. You do not need an internet connection.

Good luck, hope it helps,

Jen

Success: I resolved this exact problem. When trying to install High Sierra, my Mac was stuck the black startup screen, stalling at either 90% or 100% completion between restarts.

I managed to get High Sierra installed without losing any of my files. Here is how I did it.

Failures:

• Resetting a billion times.
• Resetting PRAM.
• Resetting CMD.
• Using Safe Mode.
• Using Recovery Mode (It would freeze upon attempting to re-install the OS, and Disk Utility couldn't detect my drive).
• Using Internet Recovery Mode (Same as above).
• Looking at Verbose startup mode -- it said "Error 13" on the drive IO.
• Talking to the "geniuses" at an Apple Bar, as well as online tech support. They suggested either formatting my drive, or even buying a new drive. They had no inclination to dig into the problem and actually figure it out and fix it.

What worked:

• I put my Mac in Target Disk mode (hold down T upon startup).
• I connected my Macbook to another Macbook using a Thunderbolt cable. The other Macbook must be running High Sierra. If you don't have a friend with a Macbook, you might be sh*t out of luck.
• I made a backup of my files, in case things went poorly. My Macbook appeared as a drive on my friend's High Sierra computer, but dragging files over in Finder resulted in an error. I had to use Terminal and "cp" my files over.
• I opened Disk Utility on my friend's computer, and here are the steps I took:
  • View -> Show All Devices
  • My Macbook showed up, along with various "Container disks".
  • I ran First Aid/Repair on all of the various things I saw. Some of them threw errors and refused to repair, but that seems to have been okay.
• I then created a bootable USB installer as per How to create a bootable installer for macOS - Apple Support using my friend's computer.
• I ejected my Mac, disconnected it from the other computer, and booted my Mac onto the USB booter. I ran the installer from the USB stick, and it succeeded! After it completed, High Sierra booted up, and all of my files were present, unharmed.

This was a huge headache for me, and I hope that this writeup helps save your files. Don't necessarily listen to the Apple "geniuses" who say that a format is necessary.

I had the same thing with MacBook Pro getting quite warm and stuck on progress bar with no other info like time remaining. I finally held down the power key until it turned off and then powered back on. It resumed the install and finished fine. YMMV and obviously bad things could happen but after this much time, you're likely going to have to do this anyway. Good luck.

Try a hard reset: press the on/off button until the system shuts down (± 5 seconds) and power back on. The process should continue where it was left before the boot, but in my recollection about installing High Sierra it now finishes the install swiftly.

I was able to solve this and successfully update to High Sierra by booting off of the recovery partition (hold Command-R while booting up).

Hya all, i was in the same spot as others here, my install stalled at around 80-90% and was silent (no HD noise). i left it overnight and it made no progress, so after reading this thread i decided to brave the restart,

just a note in addition to the great help found in the thread :

restarting was simply holding down the power button to force the mac pro to shut down,

and on restarting the mac had 'remembered' the spot it got stuck (the progress bar screen was at the same place)

then it seemed to pick up where it left it, and proceeded without any more problems.

thanks for the advice and the help that let me proceed with a little confidence!

I have this problem and phoned Apple support and the outcome was that my MacBook Pro of 2011 is too old for this update, and to get it cleared and restart I had to delete everything and re-install. Luckily I have time Machine backup, but it took ages and cost me a day's work.

Try a power down and restart. If that does not work, then a Safe Mode start. After that, boot to the Recovery Partition for some disk checks and various recovery options.

Thought I would share what worked for me on my Macbook Pro 2016 with TouchBar.

Had the same issue. Tried upgrading directly from the installer, from recovery mode, from internet recovery mode, doing first aid in between, still no success.

Couldn't login anymore, so after recovering from Time Machine (5 hours... ugh) I created a bootable usb version of the installer. This was about 45 minutes ago and I'm already here writing this in High Sierra. Give this a go!

I had the same issue when upgrading a 2011 MBP. After two hard reboots because it sat there for hours on end, it just went into a loop. Finally had to do a network boot, ran Disk Utility to check the hard disk was OK (it was), and then installed HS successfully in a couple of hours, followed by the upgrade to 10.13.1. I notice there are still a few issues, so I wouldn't recommend installing HS until at least 3 or 4 upgrades have emerged.

It doesn't do a thing unless you tell it to. I'd use it to run Disk Utility > First Aid and if the report is OK, try installing High Sierra again.

Dewey are you saying you started the upgrade on the 17th and still not recovered your machine yet thats terrible I lost a couple of days but then stupidly I tried the update twice, what a fool. What I did with mine was unplug and leave for 15 seconds then plug in hold the combination to start in recovery mode turn on weight till the useless hang page appeared then released the keys and wait for a few minutes and eventually it started in recover mode.

On top of my screen right now says "Upgrade to macOS Sierra" oh yes you bet I will click install again and lose everything for another day or two, no elfin way. Until apple say the upgrade will work on 10.12.6 I will NOT be upgrading again, thanks apple and why no response.

Good luck Dewey

You can restart and it should pick up from where it left off. Restarting in Safe Mode is a good idea.

Calling Apple support would be best

https://support.apple.com

the connected device thing is rarely the sole cause and many times it's not even a cause but sometimes it very easy to unplug and rule it out. I'd try the reboot. Not too many posts about the installer taking out systems but maybe more reports later. I'm about to let 'er rip in about 35 minutes or less.