Mega problems with iOS update

[cpittman]

I tried to update my 2012 (I think) MacBook Pro with the High Sierra iOS. The installation stalled, so I turned the computer off after waiting 15 or 20 minutes with no progress. Now, I can't restart the computer. I can sign on with my user ID and password, the restart begins, then is interrupted with an error message that is headed panic cpu3 caller. Has anyone else encountered this? Any ideas how to fix it?
Thanks,
C Pittman

 

[Hatori360]

I tried to update my 2012 (I think) MacBook Pro with the High Sierra iOS. The installation stalled, so I turned the computer off after waiting 15 or 20 minutes with no progress. Now, I can't restart the computer. I can sign on with my user ID and password, the restart begins, then is interrupted with an error message that is headed panic cpu3 caller. Has anyone else encountered this? Any ideas how to fix it?
Thanks,
C Pittman

I tried to help a work friend figure out why her MBP mid-2012 stalled on upgrade from Mavericks 9.5x to HS 10.13. Read a lot of posts on forums that mirror your issues. Had to restore her 9.5x version with Time Machine. I will try to install HS from the recovery environment using TM. I think it is a file system compatibility issue or 3rd party app issue, such as Spotify, browser addons, and other 3rd party stuff. I read about lots of fixes, but try the power reset method - seems to fix issues for some. Simultaneously press:
Shift + Control + Options + Power button for 10 seconds to power off your MBP. Wait about 20 seconds and then power back on. This is supposed to clear the System Manager Controller and continue your installation. If not, try installing HS 10.13 in Internet Safe Mode. At restart, press Command + Option +R and hold those keys down until the spinning globe appears, then install OS from there. Good luck.