The macOS 11 boot loader doesn’t work natively with the 2012 and older hardware and that means there is no recovery from this - nothing short of a complete wipe and reinstall of the correct OS, or pulling the drive mounting via external USB/thunderbolt sled and pulling your data off would bring the machine back to life. Our senior data center technician, Justin Weathersbee, found that after installing Big Sur on a 2012 Mac mini, the machine wouldn’t boot. This incompatibility with 2012 minis was confirmed during our beta testing. We knew from the get-go (thanks to 9to5Mac for sharing a compatibility list!) that Big Sur will be compatible with only 2014 and later Mac minis. We’ve been testing the macOS 11 betas from the very beginning to provide you with the best information and we have a word of caution for 2012 and earlier Mac minis. We know you’re thinking about updating your machines ASAP. Like most of you, we’ve been anticipating the launch of Big Sur - and it’s finally here.

Will late 2012 mac mini run wmr apps