Mac OS Big Sur Update issue

This morning I was given the Big Sur upgrade notification. I was a little worried but after a TimeMachine Backup gave it a try. Install took a bit longer than mentioned on the screen. Machine rebooted and gave the Apple logo with progress bar. After that it rebooted again and now it looks stuck at about 30% progress with mouse pointer.
It is like this for about an hour now on my 13" Macbook Air 1.6GHz (2017?)
Should I wait a bit longer or go for the reset? I'm coming from Catalina.

John

Thanks to jssilva and K-Berg on this thread!
https://developer.apple.com/forums/thread/649956
Trying to help signal boost, as this fix should be easier to find!

My update from Catalina was stuck, on iMac (Retina 5K, 27-inch, 2017) for many many hours.

I am not a developer, but had this problem, while installing the BIG SUR public release. It got stuck for hours and hours at about 90-95 percent. I even let my iMac sit overnight, no movement from the black screen with apple logo.

But then I did as they suggested below, power off, then back on while holding buttons to reset NVRAM.and now everything is working great! Thanks again.

I knew I shouldn't update the OS. Now I can't even start my iMac. It shows the apple logo and powers down again. It's a real shame for Apple to launch this buggy update. I tried holding down opt+command+p+r and it doesn't work. It's a real scandal that we have to go through this suffering every time we update the OS.

The only way out of this for me was to login into Recovery MacOS (by keeping cmd+r pressed during reboot), then format the Macintosh HD (inside Disco Utility) and finally re-install Big Sur (again from Recovery MacOS). The main drawback is that all my apps (either purchased or downloaded for free) were erased by Hard-Disk formatting.

I experienced the same issue, stuck at 95% on Big Sur update. I cleared the NVRAM and worked for me!

I have a MacBook Air and I’ve waited for the update to download for an hour but it didn’t finish so I tried doing the NVRAM reset and now it would log in and show the progress bar at 40% then restart itself. It would constantly restart itself, I’ve tried the MacOS recovery too but that didnt work. I don’t know what to do now

Same issue here, it was frozen at 95% for about an hour and half then I did the trick of clearing the NVRAM and now it is frozen at about 40%, no clue what is happening

selling the mac and buying a new laptop with windows did the trick for me ¯\_(ツ)_/¯

I also bit the bullet and force restarted after letting my laptop sit with a black screen overnight. I could still hear some process working, but after reading on this forum that someone had some luck with restarting I went ahead and did it. I did a regular restart without resetting anything through extra key commands. I got a progress bar with an apple after restarting, then another progress bar and apple. Then another progress bar and apple. I force shutdown again, then used the opt + cmd + p + r keys during startup. That did the trick.

I know this is old, but I just had the same issue with an old 2014 Mac that I was updating this week. (I wanted to update due to recent security fix, even if it means losing old Microsoft office.) After installing the update, my computer would not boot and was stuck at 25/30% on black screen. I waited hours and then tried to reinstall BigSur overnight with no luck. Then, I decided to try the disc utility (and back everything up before I did since before the update I didn’t think it would have trouble!!). It did need some minor repairs. I then reinstalled Big Sur, hoping that would work, but it was still stuck. I also did opt + cmd + p + r, but still nothing. Finally, I restarted it into safe mode (shift on start), which made the progress bar go farther, and now finally it is unstuck. Hallelujah! Though now it is making me recreate my account totally and was going through setup part very slowly too. My computer was working fine before- it was slow but at least worked well enough for browsing. I’m just glad I didn’t lose my machine or files (at least as of now) in this process. It is finally back to the normal desktop screen, but I haven’t restarted it yet.

My computer updated to 11.5.2 and has not booted since. It has been over a month and still no luck. I cannot access my stuck to backup to erase it and start over. Very frustrated, I have tried everything and still not luck. Starts in safe mode, but my stuff is not there to back up. Need assistance. Took it to the apple store and they said they could fix it but it would wipe all my stuff away. This is ridiculous

I’ve found it critically important to unplug all peripherals that aren’t needed. I’ve been in reboot loops that never stop! I have yanked the USB cables as the machine shuts down and gotten back to progress.

Now I always unplug the unneeded external drives before starting upgrades.

I’m writing this as I stare at a white Apple logo going from Mojave directly to Big Sur on my Late 2013 Mac Pro, wondering if it is hung…

Hi, I've spotted the same issue, and I needed to get back my files that were stuck somewhere in the system. My steps to fix that issue - I've followed the steps with reset NVRAM, which didn't work for me 30% of the progress, and it stopped. Please read step by step to save your files from being wiped out.

1. Turn off your Mac
2. Start with the pressed Shift button https://support.apple.com/pl-pl/guide/mac-help/mh21245/mac
3. Log in to Your profile and wait. There will be steps like on the new mac with all configuration steps. Don't be afraid your files are safe.
4. When You get a "new" profile. Go to the terminal and find your previous account. You can copy those files to that new profile. (please check that in the terminal guide)

https://support.apple.com/guide/terminal/manage-files-apddfb31307-3e90-432f-8aa7-7cbc05db27f7/mac

cp -R ~/Documents/Expenses /Volumes/Data/Expenses

1. To backup files, you need to use some cloud storage (in safe mode, you can't use an external drive). https://support.apple.com/guide/terminal/manage-files-apddfb31307-3e90-432f-8aa7-7cbc05db27f7/mac

2. When you copy files to cloud storage, You need to do a new clean installation of Big Sur https://support.apple.com/en-us/HT204904

I hope that will help someone