Late 2013 27 IMAC will not restart or shutdown

[Jmdadams]

Good day all,

I recently acquired a late 2013 iMac 27 from someone who was no longer using it. I purchase a WD Blue SA510 SSD to use as the main drive. Ive run into an issue where the computer will not shut down or restart without myself hitting the power button. It first occurred during a clean install of MacOS, it would freeze so i would hard reboot it and then it would finish installing. Once the software was installed I still wasn't able to restart or shutdown without holding the power button. I enabled verbose mode and this is what's shown when i try to shutdown. I'm not super technical so i don't understand it. Thanks in advance!

 

[eyoungren]

I found this: https://apple.stackexchange.com/que...-problems-x86platformplugin-result-0-messages

Any external drives, Thunderbolt docks or adapters to eSATA?

 

[Jmdadams]

Only thing that is connected is the external SSD used as the hard drive.

 

[eyoungren]

Only thing that is connected is the external SSD used as the hard drive.

Then according to that link I gave, there is probably some issue with the interface of that drive.

Try another external drive by a different manufacturer - or install an internal drive.