What was in the September 24, 2020 update that killed my iMac?

What was in the September 24, 2020 update that killed my iMac? I just turned it on this morning and it said it needed to restart to install updates, so I let it. That was 4 hours ago, and I still can’t get it to boot completely! I’m still running Mojave.

iMac, OS X 10.10

Posted on Sep 26, 2020 11:25 AM

Reply
43 replies

Nov 2, 2020 7:34 PM in response to IanAllen

Have you tried booting into safe mode?


Try a safe boot.


    Shutdown your machine.  Hold down the shift

key.  Poweron.  The boot up will take longer than normal

because the filesystem on the startup drive is being checked and

repaired as needed.   All about safe mode including what

features and apps safe boot leaves out. 

Safe boot uses a software driver instead

of using your machines video hardware.

http://support.apple.com/kb/ht1455

Sep 29, 2020 1:11 PM in response to Maineac99

I read this reply just now:


VikingOSX

User level:

Level 9

(65,581 points)

macOS

Speciality level out of ten: 1


Sep 29, 2020 1:20 PM in response to Starman35

It knocked the socks off my 2014 MacBook Air that was working perfectly with Mojave 10.14.6 before the 2020-005 update. I booted into Recovery and performed a Disk Utility First Aid, rebooted into Safe Boot mode and emptied the entire ~/Library/Caches folder contents, and then rebooted normally. At that time, I emptied the Trash.


Once the above was done, the Air returned to normal functionality, more or less…

Sep 29, 2020 5:52 PM in response to admiral_koa

I’ve never needed to restore more than a file or two from Time Machine, and to boot into recovery mode you have to hold 5 keys and stand on your head at the same time, right? I’m going to have to Google instructions. I’ve got some people telling me it could mean future hard drive or RAM failure... but if it’s just the software that’s the problem, that would save me some money. If Apple is at all likely to fix it, I hope they do it soon!

Sep 26, 2020 2:13 PM in response to starplot

This is going to sound strange, but my iMac is beginning to behave normally again. I have no idea why this is happening. It's been about 4 hours since I last rebooted. Apps are opening quickly. Pdf's are opening - until about 30 minutes ago I was getting "could not be opened because file does not exist" - now it does. Textedit opens as usual. Games open as usual. Multiple browsers open simultaneously. Two hours ago, all was NUTS. This is the weirdest update I've ever encountered. Maybe my computer is sobering up...? Maybe the system just needs LOTS of time to deal with the update.... As of now, it's running just as it did yesterday. Totally weird....

Sep 27, 2020 6:06 AM in response to Alexei Belochitski

Well, I spoke too soon. Booted up today and it's been 1 1/2 hour and I'm still waiting for it to open a single email. I'm here today on my phone (android).


What makes the system go bezirk is that it registers each keystroke and click: it just takes about 20 minutes to execute. So if I click too often on something because of no response, each click is cued up to bite me later. For example, a "force quit" that didn't seem to register ends up happening half-hour later. Then Safari suddenly opens (clicked that an hour earlier) . Apps are opening and closing, seemingly at will but it's just because it's SO FFING SLOW.


This is a 2016 system. My old 2007 Tiger iMac is still running beautifully. Instant response. The only reason I bought a new one is because of internet access. Old Safari won't work there anymore. Garageband is better on the 10.4 Tiger. New one is a joke.

Tiger was the best system Apple ever made. From that it's been downhill.

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What was in the September 24, 2020 update that killed my iMac?

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