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bryanbenjy Author

Level 1

5 points

MacOS Sierra bricked my iMac

So yesterday my 2014 imac prompted me to install MacOS Sierra, which I did, leaving it installing at 5.30 when I left work with approx 33 mins remaining.

I Come into work this morning to be greeted with the following screen:

I've tried turning it off and on and trying to boot in safe mode by holding shift when turning on, but nothing makes a difference, this comes up as soon as I turn it on and nothing makes it go away? It's flickering but not moving and nothing seems to make it respond.

Desperate for any suggestions!

iMac, macOS Sierra (10.12)

Posted on Sep 22, 2016 2:28 AM

Top-ranking reply

LucoBrasi

Level 5

5,702 points

Posted on Sep 22, 2016 2:32 AM

This looks like hardware issue for me. Try to reset SMC settings and NVRAM

Reset the System Management Controller (SMC) on your Mac - Apple Support

How to Reset NVRAM on your Mac - Apple Support

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36 replies

Csound1

Level 9

60,033 points

Sep 23, 2016 11:49 AM in response to bryanbenjy

bryanbenjy wrote:

Yes, I get a chime and I have a wired keyboard anyway. I will try that, I thought it was shift that put it into safe mode?

But when I had the second display working earlier, I was using it fine, so it appears it did the update fine, if anything it's just the driver for the iMac display which isnt working, or worse a hardware failure.

It is Shift, not Command-R which loads Recovery. And not Shift-R either

Csound1

Level 9

60,033 points

Sep 23, 2016 11:50 AM in response to DarranPotter

Wrong again, it is Shift (only) not Shift R

Trstam

Level 1

34 points

Sep 23, 2016 12:29 PM in response to Csound1

Disk utility is not good at repairing while the OS is loaded. You could try booting into single user mode by holding command S at the chime and then run /usr/sbin fsck -fy or /sbin/fsck -fy

This has fixed bad drives for me in the past.

http://www.howtogeek.com/236978/how-to-repair-disk-and-file-system-problems-on-y our-mac/

bryanbenjy Author

Level 1

5 points

Sep 23, 2016 5:05 PM in response to Trstam

is there any way of having the Apple diagnostic tool displaying on an external monitor for an iMac?

my iMac display isnt working, horizontal lines coming up as per other thread, but I can't run the diagnostic test because it runs it before powering on an external display and I just can't see anything on my iMac screen.

so wondered if there was a way of getting the diagnostic tool to run without the iMac screen?

Nov 7, 2016 12:13 PM in response to bryanbenjy

I had my Macbook Air 'brick' this last weekend after installing an app. It would no longer boot..... even tried the command-R and ran disk utilities ...... NO luck...... I had to drive to another town there they had high speed internet at the library in order to reinstall osx. THIS time I will keep an installer on a USB drive (Using Diskmaker X v6) ..... just a heads up. This version is dangerous. (by the way I had this happen with the beta I was testing too but disk utility would always bring it 'back' ..... NOT this time !!! ) .......... yikes !!!

Nov 30, 2016 11:59 PM in response to bryanbenjy

I had a very similar issue. It would boot up, then about half way though the cycle the screen would flash and display a horizontal coloured line about a inch from the top of the screen. It would then go black and the wheel would periodically flash on and off. I have managed to boot up by going through to disk utility and changing the startup disks to the external drive, on which I have downloaded El Capitan. Luckily I had access to another machine to do this. It still seems to stop temporarily half way through booting up but quickly continues right through to the end, so Sierra is the problem. I am now in the process of backing up files from the HD before performing a clean install of El Capitan. If i had made a back up before Sierra this process would have been a lot easier! IMAC 27" Mid 2011 i5

MacOS Sierra bricked my iMac