Random reboots

Sh@ne Said:

"Random reboots: My Mac mini 2018 has been randomly rebooting. I tried to upgrade to macOS Monterey in an attempt to fix, but it failed to run. I also can't boot into Windows anymore. Running first aid in Disk utility spits this out which makes me nervous:"

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Reinstall the macOS:

The volume is apparently corrupt.  So, reinstall the macOS. Nothing would be lost. It's just that misplaced items would be placed back to where they should be and corrupt system files would be replaced by clean files. Go Here: Reinstall macOS - Apple Support. Prior to the reinstallation, to prevent data loss, be sure to back up your Mac with Time Machine, so that you can have something to restore your Mac from, should anything happen after the reinstall.

TheLittles wrote:

Reinstall the macOS:

The volume is apparently corrupt.  So, reinstall the macOS. Nothing would be lost. It's just that misplaced items would be placed back to where they should be and corrupt system files would be replaced by clean files. Go Here: Reinstall macOS - Apple Support. Prior to the reinstallation, to prevent data loss, be sure to back up your Mac with Time Machine, so that you can have something to restore your Mac from, should anything happen after the reinstall.

FYI, the partition table is corrupt, not the volume so reinstalling macOS over top of itself will not help. At best reboot into Recovery Mode or from a bootable macOS USB installer and attempt to repair the partition table using First Aid on the physical drive again (Apple SSD Media.....). If First Aid is unable to repair the partition table while booted to the installer, then the whole physical drive needs to be erased as GUID partition and APFS (top option) before reinstalling macOS and restoring from a backup.

Those large negative error codes indicate a network issue of some sort when booting into Internet Recovery Mode. It is best to connect the Mac directly to the router using an Ethernet cable for a faster more reliable connection that bypasses any hard to troubleshoot WiFi issues. You can also try power cycling your router (wait at least five minutes for your router to finish booting). You can also try a PRAM Reset in case the Mac is stuck booting to a previous location regardless of your selection of startup keys (hold the PRAM Reset for at least two chimes). Sometimes your router settings or your ISP can interfere with being able to boot into Internet Recovery Mode.

As for the Mini booting into Internet Recovery Mode when booting from the USB installer, this is likely due to the fact you probably never modified the Mac's security settings to allow booting from USB. When you attempt to boot from USB without first configuring USB booting, the 2018+ Mac will boot into Internet Recovery Mode so that you can authorized the Mac to boot from USB. See this Apple article for details:

About Startup Security Utility on a Mac with the Apple T2 Security Chip - Apple Support

Or it may mean the USB installer stick you created has a problem. Macs can be very picky about the drives used for booting plus the quality of USB sticks is extremely poor (even from reputable brands). You can try using another USB stick (especially a different brand), and also try using another USB port and/or adapter as well. Connect the USB stick directly to the Mac and even disconnect all other external devices which are uneccessary for this process.

Also, make sure to use the instructions in this Apple article for creating a bootable macOS USB installer:

How to create a bootable installer for macOS - Apple Support

Make sure to download the installer directly from Apple. Using any other installer or using any other method for creating the bootable macOS USB will most likely fail (from posts I've seen on these forums).

HWTech Said:

"FYI, the partition table is corrupt, not the volume so reinstalling macOS over top of itself will not help.[...]"

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Saying "apparently", it appress that way, by description. So checking the volume through use of First Aid in Safe Mode is what I am getting at. So, the OP should do that, seeing if such is the case.