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Catalina Not Happy With 2012 iMac

TL;DR - Installer Stuck, Multiple Attempts, Recovery Mode, Erased Drive, Installed Clean 10.14 (Old Mojave), Migration Assistant Time Machine Backup Restoration, Back To Working Mojave.


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I attempted to upgrade from Mojave to Catalina. Seemed to be installing slowly but surely. A few hours into the install process I peeked in and saw the iMac was stuck in a loop of restarting, throwing an error 10 seconds later 'Your computer restarted because of a problem. Press a key or wait a few seconds to continue starting up.' and then restarting again only to throw the same error again.


I made sure I had well over 10GB of free space for the system to work with (writing temporary files, moving data, etc). I forced the machine off by holding the power button. I disconnected any external drives (including backup drive). I booted into recovery mode by holding command+r at the boot chime. I tried to install a clean version of Catalina from recovery only to get stuck again, even after running First Aid with the Disk Utility.


I had a Time Machine backup external drive so, still in recovery mode, I launched Disk Utility and noticed there was a new Macintosh-Data volume. I deleted it. I then installed a new clean version of 10.14 (Mojave) onto the normal Macintosh volume (which in my case is the 128GB SSD + 700GB HDD in one logical Fusion volume). The other 300GB of my internal 1TB HDD is partitioned for Windows 10 Pro. I reconnected all my external drives (along with backup drive). I logged into the newly installed Mojave, launched Migration Assistant, then restored from my latest Time Machine backup.


My iMac is back to running Mojave. I will be on the lookout for future updates but let this post be a reminder to those with older hardware (Late 2012 iMac, 3.1GHz i7, 16GB RAM, Fusion Drive, NVIDIA GeForce GT 650M) that Catalina may give you a bit of trouble, and to BACKUP your system with Time Machine prior to trying out this new update.


Cheers

iMac Line (2012 and Later)

Posted on Oct 9, 2019 4:30 PM

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Posted on Oct 9, 2019 4:52 PM

I have nearly the same iMac (only difference is the processor, mine is 3.4 GHz Quad-Core. My install went okay, but man, the computer has slowed down a LOT. Things that used to be pretty fast in Mojave are very sluggish in Catalina. I see the spinning beach ball frequently now.


Not sure why your install was such a mess, maybe the Windows partition gave it problems? I know these Fusion Drives have been problematic, but so far I haven't had any issues with mine. Glad you got everything back to the way it was. I hope Apple has an update soon to fix these problems, this is one of the buggiest OS releases I've seen in a long time. I'll probably go back to my policy of waiting until the x.1 release of a major OS version like I did in the past.

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Oct 9, 2019 4:52 PM in response to Daft Puzzler

I have nearly the same iMac (only difference is the processor, mine is 3.4 GHz Quad-Core. My install went okay, but man, the computer has slowed down a LOT. Things that used to be pretty fast in Mojave are very sluggish in Catalina. I see the spinning beach ball frequently now.


Not sure why your install was such a mess, maybe the Windows partition gave it problems? I know these Fusion Drives have been problematic, but so far I haven't had any issues with mine. Glad you got everything back to the way it was. I hope Apple has an update soon to fix these problems, this is one of the buggiest OS releases I've seen in a long time. I'll probably go back to my policy of waiting until the x.1 release of a major OS version like I did in the past.

Oct 9, 2019 5:44 PM in response to TomNYC

Ah, glad to hear it went well on your similar system - brings me hope :) I too wonder about the extra partition being problematic.


I can't help but think the Catalina slowness is a combination of the newer Apple File System (APFS) format that is tuned for solid state drives but running on a Fusion drive with a mix of spinning hard disk drive. Or maybe data is still being greatly moved around as the system optimizes itself.


I will be adopting that x.1 policy this go around!

Oct 14, 2019 9:42 AM in response to paleohunter

I am also having all kinds of issues with my late 2012 iMac. I have tried to install Catalina 2 times. I have tried a completely wiped HD and building my profiles from scratch and also tried updating over Mojave and migrating my profiles and both have resulted in issues.


First issue: iCould Drive no longer syncs or even shows the folders, yet if I try to create a new folder using the same names i used before it says the folder already exists even though I cant see it. New folders with new names never sync.


Second issue: Mail fails saying the Home folder is not large enough to download messages. There is 300GB of available space on my drive.


Third issue: Cannot down load any file, or duplicate any file larger than 20MB. Get an error message that my Home Folder does not have enough room. Again I have 300GB of available space.


Fourth Issue: Photos and Music in a continuous loop of trying to sync pictures and music files. Sync never completes and keeps starting over.


I am starting to wonder if these issues are specific to the hardware on the 2012 iMac as others do not seem to have this issue.

Catalina Not Happy With 2012 iMac

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