Mac Mini 2018 (A1993) Won't Boot

[samuelkastning]

Hello Everyone,

I have a 2018 Mac Mini that will not boot. It originally had MacOS Catalina and needed to be reimaged. Here are the steps I have taken with the results:

• Booted into local recovery and wiped the drive.
  • Was no longer able to boot into local recovery.
• Booted into a MacOS Installation USB with 15.7.4 on it.
  • Was kicked to Internet Recovery.
• Tried booting all three keyboard commands for internet recovery.
  • Tried 3 different Networks with 3 different ways of connectivity. (Wifi, Ethernet, and USB with IPhone Hotspot)
  • Each way gave me an error: -2006F, -2003F, and -3403F.
• Booted into MacOS Installation USB with 12.7.4 on it.
  • Was kicked to Internet Recovery.
• Restored BridgeOS Firmware with DFU Mode.
  • Tried all above steps again (Minus Local recovery), all failed the same way.

I have no idea where to go from here, and from looking across the internet, I can't seem to find anything. I know it's likely something to do with the T2 security settings, however I cannot get to Local Recovery to be able to change those settings.

 

[samuelkastning]

Alright, after FOUR attempts at Internet Recovery with my hotspot i was finally able to get it to boot (Command +Option +Shift + R), and am installing MacOS Catalina.

 

[jeffreyadik]

I ran into a similar problem... fortunately I had an older MacBook Pro (2014) running Catalina. The following ideas stem from @samuelkastning journey.

1. I used Carbon Copy Cloner v5 (free trial download available at https://bombich.com/) to create an external drive bootable clone
2. I booted this clone on the Mac Mini 2018, pressing & holding the "option" button immediately after the chime.
3. After successfully booting into the Catalina clone on the external drive, I used disk utility to wipe the Mac Mini 2018 internal SSD (only format option was APFS)
4. On the App Store, I searched for "Sonoma", downloaded and ran the installer, targeting the Mac Mini 2018 internal drive.
5. The installation was successful, and the Mac Mini 2018 successfully booted to a virgin installation of the final release of Sonoma.

This approach, of course, requires a functional older model Mac, or a bootable live macOS external drive. Hopefully it will help someone else.