Machine rebooting on start-up with more than one user profile?

[Steve121178]

I don't have this issue on my M1 MacBook Air, but on my late 2013 MacBook Pro, when I freshly boot the machine up and its ready to login, I start entering my credentials and the machine will reboot by itself before I get a chance to fully enter my password.

So, the process at the moment is to boot my MBP up until its at the logon screen, leave it for 20 seconds & wait it will reboot on its own and when it comes back up only then will allow me to log in.

I read on another site that this issue is caused by FileVault. I naturally assumed this is a known issue on older Macs and I figured the next update would fix this. After installing 11.2.3 this issue is still present.

Any ideas on how to fix this? It's driving me nuts.

Also backing up to Time Machine is painfully slow & even worse on my M1 Mac.

Frustrating.

 

[appltech]

When FileVault is enabled, first it presents a "fake" login window in order for you to enter the password and unlock the hard drive to boot from. Yes, indeed, it seems like at this stage something goes horribly wrong.
I'd try disabling FileVault just to check if it is indeed to blame. If it is, try enabling it back and see if the problem returns.
Then, I'd go for a generic OS reinstall via Recovery Mode.