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Progress Bar Stuck on 100% on boot High Sierra

I have a Mac Mini (Late 2012).


Last month I upgraded the memory from 4GB to 16GB and installed macOS High Sierra; am currently on version 10.13.1


Yesterday (11th November 2017) I booted up my MAC at 9 am (ish) with no problems, during which time it successfully backed up twice to Time Machine at 9:15 and 9:50.


I shut down not long after this, then booted up again at about 13:10, and noticed the usual progress bar beneath the apple symbol was taking a particularly long time. I did a hard shut down and restarted, and still it took a long time, so I left it, then after about 20 (far longer than usual) minutes, it reaches 100% and stayed there: no log in screen.


I shut down and tried to reboot in Safe Mode (holding shift after the chime) but this made no difference as I never got to the log in screen.


I reset PRAM/NVRAM by rebooting and holding command+option+P+R at the chime. Nothing.


Reset SMC (unplugged, held power button, released, plugged back in) still no log in screen after 100%


I booted into recovery mode, opened Disk Utility and checked my hard disk. It returned ok with no errors found. Rebooted, still stuck at 100% with no log in screen.


This is where it starts to get scary.


I rebooted back into recovery mode, and reinstalled High Sierra (took about 3 hours), and, incredibly, it DIDN'T FIX THE PROBLEM!!(still can't believe this!!!) After installing, it rebooted, and again after half an hour the progress bar reached 100% and stayed there: no log in screen! How can actually reinstalling the entire operating system NOT FIX a start up problem? Does it not overwrite the system files it needs to reboot? I just don't understand how this is possible!?


I then went to bed and left my MAC on overnight. In the morning (about 7 hours later) still apple symbol with progress bar at 100%; no log in screen.


I booted in Verbose mode (command V) and saw lots of crashed processes "producing too many corpses"


I decided at this point to restore from a time machine back up. I didn't chose the ones from the morning before because it was after these back ups that my mac wouldn't restart, so opted for the back up the night before because I successfully restarted after this the following morning.


It took 8 and a half hours.


When it had finished, my MAC started just like it had before the problem occurred and everything was back the way it was before anything had happened.


The point is: I am now absolutely terrified to shut my mac down. I did nothing - install any new software, download anything etc - between booting up yesterday morning and yesterday afternoon which would have caused such a critical error, and I just can't believe that I couldn't boot into safe mode, and reinstalling High Sierra didn't fix it (still can't get over this), and am not going to be able to shut down until I know what caused it because I can't wait 8 and a half hours every time I need to use my MAC!!!


I read some articles about kext files, and booted in Verbose mode and saw some error messages about crashes and "too many corpses". I've also in Terminal compared the current system library with the one from the last back up that I successfully booted from and it's only found very few differences - mainly mobile assist fonts, and only 8 cash files - which is really surprising; are the files needed to start up kept somewhere else other than System/Library? I also read that other people managed to log into their macs after restoring from a back up like I have but after the next restart the problem still occured and they couldn't get back in.


Could all this have been caused because I interrupted it when it was being slow to start the first time? But why would it suddenly take so long to start when I haven't installed anything new, and there hasn't been any updates?


Would it be safe to wait for the next update and shut down then?


Is there any danger in leaving your mac mini on for a long time? (fan, heat etc)


Obviously the longer I leave it, the more data I will lose as I will have to restore from the last back up before the problem occurred which is currently the 10th of November, if it won't start again.


Anyone had the same problem and found a fix? Is it now safe to restart? I head something about Kext files in the Extensions folder and moved them but it didn't fix my problem. I can't think of anything I did between 9am and 1pm that would cause such a slow start up followed but such a fatal error; I installed High Sierra over a month ago, and installed the last update over a week ago.


What could High Sierra have done on it's own in the background between 9am and 1pm that now prevents it from starting up?


HELP!

Mac mini, macOS High Sierra (10.13.1)

Posted on Nov 12, 2017 1:12 PM

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Question marked as Best reply

Posted on Jan 19, 2018 11:37 AM

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.

148 replies
Question marked as Best reply

Jan 19, 2018 11:37 AM in response to fpuk69

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.

Dec 7, 2017 3:52 PM in response to fringeli

After starting in Safe Mode, disk utilities and erasing the hard drive, then using Time Machine to get back to where I was, I got a clean start. I uploaded Malwarebytes (free malware hunter) and found a virus. It also sequestered an app called Ad Block Master. I removed both. Haven't had any trouble since. The virus was using up nearly all of my RAM making start up impossible. My processing speed is back to normal as well.

Dec 18, 2017 5:52 AM in response to jeff work

Booting into safe mode allowed me to track down & remove the kext's that were causing my problems.

User uploaded fileUser uploaded file.

However, I think there is a combination of things happening here starting with how Apple is handling these kext problems when booting (after beta 4 10.13.2). I haven't definitely identified these changes and hopefully someone with more expertise can id this changes. 1. When booting in 10.13.2, decrypting the boot disk the progress bar sticks at 100% or less, I believe APFS my not be "clearing" errors or past problems with kexts, and isn't continuing with the decrypt. Booting into safe mode may "clear" these problem flags after the problem kexts are removed & allow decrypting to continue. 2. It may be connected to the "snapshots" APFS is creating. 3. When I change my boot volume back to HPFS, I don't see these problems.

I have had more problems with High Sierra than any other OSX versions. I would recommend if you need to run it, use HPFS formatted disks for ssd boot.

User uploaded file

Jan 22, 2018 6:39 AM in response to fpuk69

FWIW… MacGallant wrote in the Slow Boot thread:


1. Go to System Preferences


2. Select Startup Disk


3. Click Lock to Unlock and enter Admin password


4. Click and select and highlight Macintosh HD


5. Click Lock to Lock back setting


5. Close System Preferences window


6. Upon reboot you should see that the boot and login to macOS High Sierra is faster again, just like in macOS Sierra and earlier!


Re: macOS High Sierra slow boot...


I did this and I've had five normal starts in a row. Worth a shot perhaps.

Jan 18, 2018 2:29 PM in response to steve626

I can't believe that Apple isn't addressing this issue properly.


I recently had problems with my Macbook Pro running slowly so Apple Support told me to update my OS to Sierra. It worked for a short while then went slow. I contacted Apple Support for some advice and we ran through a few steps. It didn't seem to make a difference. Then I went to start up one day and it wouldn't start. Same situation as others here. Progress bar taking ages to progress to 100% and then nothing further happening, even when left overnight.


My major issue is that I had just downloaded pictures of my newborn son, and had not had a chance to back them up, so I absolutely don't want to lose the data.


After numerous dialogues on Apple chat. I have:

  • Run Disk Utility in Recovery Mode - nothing found
  • Tried to boot in safe mode (it won't - producing too many corpses)
  • Checked the file system
  • Reset the NVRAM
  • Reset the SMC
  • Used Target Disk Mode (HD not detected)
  • Reinstalled macOS Sierra from Disk Utility


NONE of these steps have worked!!!


I find it hard to believe that the laptop can just stop working like this and Apple can't offer a solution. It's not what you expect from simply using the product as advised.


If anyone has any helpful advice or managed to get it to work please let me know!


Thanks

Apr 28, 2018 1:42 PM in response to fpuk69

I'm a very experienced Mac tech support consultant, yet I've been grappling with the "too many corpses" problem since yesterday. I tried a number of approaches, but was confident that a simple solution existed. YOU MAY NOT HAVE TO ERASE YOUR HARD DRIVE, or reinstall Mac OS. I found a couple of postings that explain this surprisingly quick solution. If you're able to get into Recovery Mode utilizing CMD-R, and you're not afraid to work in the Terminal program, THIS WORKS! If you follow these steps EXACTLY, a bad file named "mbr_cache" will be rebuilt and your Mac will reboot successfully (slowly the first time as the rebuild happens, then normal speed after that). This solution worked on my 2011-vintage 21-inch iMac (iMac 12,1) with Mac OS High Sierra. Someone should tell the Apple Geniuses and Tech Support Specialists about this. Or, better yet, they should be able to find these types of solutions themselves. Good luck!

The two articles where I found this solution are:

macos - Opendirectoryd too many corpses being created - Ask Different

https://mrsystems.co.uk/blogs/news/too-many-corpses-being-created


Steps from the articles:

  1. Boot and hold CMD-R to start up from macOS Recovery
  2. If Filevault is on, mount the disk with Disk Utility and enter password
  3. Enter these two commands in Terminal
  4. cd /Volumes/Macintosh\ HD/var/db/caches/opendirectory
  5. mv ./mbr_cache ./mbr_cache-old
  6. Exit from Terminal
  7. Restart the computer

Dec 3, 2017 12:26 AM in response to fpuk69

I have the same problem.


My Mac Mini (Late 2014) was originally unable to upgrade High Sierra because of the "cannot unmount disk" error, brought it to Genius Bar and did a fresh install and it was able to boot for a few times.


I then recovered my data from a Time Machine backup and in turn starts up Docker and Virtual Box, it is where it gets unstable and the VM is crashing. So I went ahead for a soft reboot, it is when it stuck at 100% on boot.


My gut feeling is that APFS is not that HDD friendly and refuse to mount every now and then.

Dec 11, 2017 12:30 PM in response to fpuk69

Had this same problem after doing my usual update procedure once High Sierra had hit .2. I wipe the drive, do a clean install, then do a migrate from a Time Machine backup to bring my stuff back. Hasn't failed...until now.


Even booting Safe Mode didn't work (would still hang). Finally ended up reinstalling High Sierra again over this newly-upgraded installation, which did the trick.

Dec 11, 2017 1:05 PM in response to fpuk69

I'm having similar problems. It started happening after beta 4 install (for 10.13.2). After installing beta 4 the next reboot resulting in a continue reboot cycle after entering the password to decrypt the startup disk. It didn't matter if I booted to the recovery partition and ran check disk or reset NVRAM. Same problem with beta 5,6 & the release version. I submitted a bug report ~ several weeks ago I got no response. With the release of 10.13.2 it caused both of my 2013& 2014 rMBP to do the same thing. Even when I used the recovery partition to reinstall 10.13.2 it didn't make any difference. I ended up booting to safe mode to try & track the problem down. I have the sysdiag dumps & trying to track down what is happening. It appears something is loading at the point the disk is being decrypted that crashes the system. Strange that it started after beta 4. Apple changed something.

Dec 11, 2017 2:12 PM in response to fpuk69

Just had the same issue. Was working fine, shut down, restarted and progress bar stuck at 100% and then went nowhere. I rebooted using my previous Sierra external drive, went to disk utilities, picked repair disk and it said found errors and after rebooted on internal drive and now OK again. Not sure how long this will last. I have 10.13.2.

Dec 11, 2017 4:24 PM in response to hamosity

And after a weekend leaving it in sleep mode, I returned to work, was able to type in my password... and nothing, just the password window and nothing happening. Finally re-booted in Safe Mode, ran Disk Utilities and supposedly it found an issue. I restarted normally and so far OK. We'll see. I've never had an upgrade go wrong. 10.13.1 seems to have glitches.

Dec 16, 2017 11:17 AM in response to concordiadiscors

First of all, I changed the DNS of my router to 8.8.8.8 after that Internet Recover start working. Before it was not working. After internet start working I tried to clean install the High Sierra through Internet. But same problem happen again. Stucked at 35%. Then I again reboot to internet recovery and format my Hard drive completely and install again. This time I was successful. ALHAMD O LILLAH

Progress Bar Stuck on 100% on boot High Sierra

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