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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 Top-ranking 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

Jan 22, 2018 6:47 PM in response to fpuk69

I have this problem, too.

After upgrading to High Sierra, I stuck in 100% process bar. But Mac did react to the keyboard or play the sound. The only way to get into systems is to use VoiceOver to guide you click restart in apple menu or just enter single user mode and text reboot... but if you attempt to boot after shut down it must stuck at 100%

reinstalling macos is useless.

Jan 24, 2018 2:05 AM in response to tigren

I gave up waiting for solution, seems there is no other way I have to reinstall OS, here is my step:


1. Buy an external hard disk.

2. Enter Recovery Mode, backup data to the disk with: File > New Image > Image from “Macintosh HD"

3. Ask my friend who has MacBook to help me create a bootable USB stick (High Sierra 10.3.2)

4. Erase my disk and do a fresh install.

5. Use Migration Assistant to recover my data. Thanks for this blog: http://www.easymacsupport.com/blog/mount-dmg-for-migration-assistant-quickly-wit hout-verification

6. Enable Time Machine to the external disk.


At last, my Mac Mini is back, no data is lost.


Wait... when all of these done, Apple released 10.13.3, but I am not sure should I install the update? What if the error occurs again?

Jan 24, 2018 10:24 AM in response to fpuk69

I had this problem yesterday after I updated my Mid 2012 MacBook Pro from Sierra at the weekend. The installation worked fine and my Mac rebooted ok at the time. I used it for a couple of days then shut it down, when I came to restart the following morning the progress bar also got stuck at 100%. I spoke to Apple support via IM and they made me do all the checks everyone else on this thread has been doing.... Safe Mode, Recovery Mode and running First Aid on the hardware etc....


Nothing resolved the problem then with another call to Apple I was instructed to reinstall the High Sierra OS from Disk Utilities in Recovery Mode. That didn't resolve the issue, so another call to Apple who I made aware of this thread, said they had no prior knowledge of this being a problem. I had to erase my Mac and recover everything from a Time Machine backup over about 3 hours - TF I backed up just before updating!


Apple really need to figure something out because erase and recovery shouldn't be the only option for an OS glitch. One thing's for sure High Sierra is definitely 'high', maybe too high to function properly for some Macs.....so keep it Sierra and leave getting high for a trip to Denver.....or backup before you do!

Jan 24, 2018 5:01 PM in response to fpuk69

This may or may not solve everyone's issues, but my new iMac wouldn't get past 100% on load, nor could I boot in safe mode. I could boot in recovery mode however, and was able to use Disk Utility. Upon first try, I only used First Aid on the Fusion Drive, but this didn't work on a reboot.


I then used Disk Utility again and ran First Aid on every drive option available. I don't know which one did it, but on reboot it started up instantly again.


Just my experience and hopefully helpful! If not, I feel your pain!

Jan 25, 2018 1:16 AM in response to fpuk69

Solved for me quite easily:

I had the same problem as many here (2015 27" iMac froze at 100% on boot with High Sierra - completely unresponsive)


Tried Recovery Mode and ran Disk Utility - nothing helpful


Simply went back into Recovery Mode (option-command-R), re-installed High Sierra from the menu presented (currently connected to fast Gbit internet) - process took about 40 minutes. All worked fine - rebooted fine, all data seem great, no immediate problems. Just hope it does not happen again.


Hey Apple - you listening? - with all your billions of profit - please plough a bit back and fix this glitch with a decent patch??

Jan 26, 2018 6:46 AM in response to McTann

I'm glad it worked for you McTann and hope it continues to. Unfortunately I'm on here again today because I thought I should mention that after about 7 consecutive good starts, my Mini (2012) choked on the boot progress bar again this morning. Twice. The second time I was trying to boot in safe mode, which it seems unable to do these days (perhaps because its dirty old M7803 keyboard doesn't work all that well by now, or the Mini doesn't like it, but I doubt those theories). For reasons beyond me, when I lost patience, let the shift key go, and pressed/held the power button, it restarted instead of simply shutting down, and the third time was the charm. Running fine now. I will try MacGallant's trick again—perhaps it serves to clean something up that will repeatedly get dirty while running under High Sierra. Frustrating to say the least. As Sejonmusic said, erase and recovery shouldn't be the only option for an OS glitch. (No, we don't *have* to erase, we can try the simple reinstall from recovery mode first, but even that's risky and extreme in my opinion.)

Jan 26, 2018 9:15 AM in response to Ashley Eldridge

My MBP situation seems more complicated. The computer was upgraded to High Sierra in early December 2017, and worked well for a few weeks before freeze. Now, clean install of High Sierra can be done smoothly for external SSD drive, but can not internally for the same drive. After the externally installed drive is swapped inside, it can not boot or get dead pinwheel for any movement if luckily booted. It seems the drive cable could be a problem. Then I replaced the old cable with a new one, and can not get any improvement. When a SSD with Mac OS X Lion (10.7.5) is input as interval drive, the computer behaves normally - as fast as before crash, which indicates the drive cable should be fine. I also tried to reversely format the drive to HFS+ and clean install Sierra. The Sierra installation internally took overnight, and the result is the same as High Sierra - can not boot. The computer is MacBook Pro 13 (early 2011; A1278) with the following features:

Hardware Overview:

Model Name: MacBook Pro

Model Identifier: MacBookPro8,1

Processor Name: Intel Core i5

Processor Speed: 2.3 GHz

Number of Processors: 1

Total Number of Cores: 2

L2 Cache (per Core): 256 KB

L3 Cache: 3 MB

Memory: 8 GB

Boot ROM Version: MBP81.004D.B00

SMC Version (system): 1.68f99


At the moment, I do not know what to blame for the problems - hardware or software, or both?


Any suggestions or clues, please!

Jan 27, 2018 4:20 PM in response to Lions1982

This just happened to my mid 2011 Mac mini, after the10.13.3 update, though since High Sierra it was never super stable to begin with.


Boot progress bar on white background got stuck at 100%, I left it on for hours and nothing happened. Found a USB keyboard to boot to recovery to run first aid on the SSD, which didn't help. Since my main Mac has Thunderbolt3/USB-C ports, I didn't really have the right cable/dongle to do target disk mode with the mini. So I opened up the Mac mini to remove the SSD, put it in a USB-C enclosure so I can use my main laptop to troubleshoot. First I booted off the external drive and it also got stuck at the progress bar, so at least it was software and not the Mac mini. I then booted up the internal drive to copy some files over just in case. After that I booted to recovery to reinstalled the OS on the Mac mini SSD. After all that it booted up fine with all the data still intact, only thing I had to re-modify was the static IP in Network settings. I put the SSD back in the Mac mini and now everything is working great again.


I guess Sierra to High Sierra upgrade has some issues so a lot of us have Macs in weird states, but re-installing was an easy enough fix. This issue is probably more prominent on older Macs that have gone through multiple macOS/OSX upgrades. I get new laptops pretty often and always just set them up as new, and High Sierra upgrade went great on my current laptop.

Progress Bar Stuck on 100% on boot High Sierra

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