iMac boot loop prohibition symbol. Startup commands not working

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iMac boot loop prohibition symbol. Startup commands not working

Hello, my late 2013 27” iMac suddenly froze and restarted the other day and is currently boot looping.

Cmd + R doesn’t progress past 3/4 nor does internet recovery, resetting NVRAM is greeted with a prohibition symbol and safe mode seems to not register entirely. From everything I’ve read it sounds like an SSD fail. Any ideas? What’s strange is that holding Alt seems to work fine and displays both partitioned drives. Booting into Windows however also gets about halfway and restarts.

The SSD was installed myself along with extra RAM. It’s been working fine with zero hitches for over a year since.

I should mention that this happened once before last week, but upon trouble shooting for a couple of hours the computer booted up completely normally! I was able to use it for a number of days by just putting it into sleep mode, however yesterday upon trying to access the windows partition I was able to use it for nearly an hour before the screen froze with some weird graphical glitches and then hard crashed. It is now boot looping for the second time.

Thank you!

Posted on May 2, 2022 8:12 AM

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Answer 1

Top-ranking reply

rkaufmann87

Level 10

143,898 points

May 2, 2022 8:26 AM in response to Tanglefoot_

You need to take the computer into your local independent Apple Authorized Service Provider to be professionally diagnosed. Please remember it is 10 years old and likely has suffered a mechanical failure so a replacement may be in order rather than trying to have it fixed which is expensive and considering it is obsolete in that it cannot run current versions of Mac OS may not be worth fixing.

However, if you want to keep it. Get an external SSD, connect using the USB connection and then restart by holding down Command + R and let it download Mac OS onto the new SSD. Then update the computer to the version of Mac OS that the computer was running before it failed. Then use your Time Machine backup to restore your data and apps and you are back in business and can likely get some more time out of the computer.

Another option is to create a bootable installer if you have another Mac (How to create a bootable installer for macOS - Apple Support) using the version of Mac OS that was installed before it failed, then install it on the external SSD and restore from your TM backup.

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Answer 2

rkaufmann87

Level 10

143,898 points

May 2, 2022 8:52 AM in response to Tanglefoot_

Sorry to hear that that. I hope you did not too, if you can get it fixed without losing your data, please begin backing up ASAP. As it is you may be facing a painful lesson on why backup is absolutely essential.

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