2019 27" iMac random restarts

Here is an article that may help.

• If your Mac restarted because of a problem - Apple Support

Please navigate to www.Etrecheck.com and download the free version of EtreCheck. Once you have you downloaded the

app and installed it, please run the report and save it. This report will help us get a good idea what has been installed on your system and help us be able to diagnose what may be wrong.

When you have your report, you can attach it when you reply to this message and we can then review it and help you determine what is needed to get your system running well again.

For instructions on how to download your EtreCheck report and attach it to your reply to this message please click https://discussions.apple.com/docs/DOC-250000211

What did you do to disable the secrurity and why is there no backup?

Your report indicates:

Apple security disabled - Apple security software is disabled. This computer is at risk of malware infection.

I suspect you may need to install Mac OS which will fill in any missing pieces. If this does not solve your problem, you will need to do an erase and install and start all over again. Without a backup of your system, that means all your data and third party apps will be lost. At the very least you should be using Time Machine to backup which only requires a external HD such as a OWC Mercury Elite Pro . Time Machine is built into Mac OS and you can learn how to backup using Back up your Mac with Time Machine.

Notes:

• No Time Machine backup - Time Machine backup not found. • Please make a backup!
• Security Disabled • Go to System Preferences > Software Update > Advanced, and select "Check for updates" and "Install system data files and security updates" at the minimum. You do not need to erase.

Cheers,

Jack

My recommendation at this point is to do an erase and install and start over.