Note
If you followed this guide before, you might want to scroll all the way down to the TL;DR version of this guide
Somehow, I managed to ”brick“ my Mac mini (2018, Intel) when I wiped its data before selling it online. From then on I could no longer:
- boot the normal Recovery Mode
- re-install macOS using an USB stick
- use the online Recovery Mode, since it always ended up in a error
-1008F
I have since wasted several hours reading online guides, trying to get it fixed. Mostly, without success. The crucial hint was in the accepted answer on AskDifferent:
By default, Mac's that have the Apple T2 Security Chip cannot boot from external media.
However, the rest of the answer didn't help much. Instead, the hint to a solution was hidden a little further below, but not directly in the answer. Alas, since my memory is still fresh, I'm trying to reproduce the solution in the following.
Ultimately, the solution was to boot my Mac in DFU mode. I came across this before, but the devil was in the detail.
Before we start, make sure you have a working Mac. We're going to call this working computer the host machine. As for the bricked Mac, let's call it the broken machine.
Of all USB-C ports on your mac, only a specific one can be used for DFU mode. When facing at your Macs USB-C ports, this rule of thumb applies:
- on Intel, the right-most USB-C port can be used for DFU mode
- on Apple Silicon, for some reason, they changed this to the left-most
From the Apple Support pages:
Finding the DFU-capable port only is important on the broken machine. Use any other USB port on the host machine. If I remember correctly, you should not use the DFU-capable port on the host.
Here's another guide, it tells you to use a standard USB-C cable – not a Thunderbolt cable. This can be the default charging cable of an iPhone 16 (and likely any other USB-C model, including iPads).
Again, there are differences based on the chip architecture of your Mac. They are explained at length in this YouTube video (ugh!).
Some of the guides I read mentioned the use of the Apple Configurator. Ignore this software for now. Make sure to open Finder on the host machine and watch it closely while doing the following.
On Apple Silicon, shut down your Mac, then power it on again while holding any of the following keys: the power button (aka Touch ID button), Control, Option, Shift. Do this for ten seconds.
On my bricked Intel Mac mini, as stupid as it might sound, I had to do the following:
- unplug the power cable
- hold the power button
- plugin in the cable again, do not let go of the power button
Once the broken machine has entered DFU mode, the focus in the finder will shift to the Mac. Meaning, it will be selected in the left sidebar of the Finder, with the main window presenting you two options: revive and restore
I clicked the latter, “Restore”.
Restoring will take a couple of minutes. But once its complete, you can disconnect the USB-C cable, reboot the broken machine and hold Ctrl+R to enter recovery mode. You should now be able to use it with online recovery successfully working again. I did format my SSD prior to that, but I don't think it was necessary.
Once completed, you should now be able to install a fresh copy of macOS. Take note that this might be an older version than the one you had before. For me it was Mojave (macOS 10.14), even though I had Monterey (macOS 12) or Ventura (macOS 13) installed before it got bricked.
- Get a USB-C cable, e.g. the charging cable of an iPhone 16. Do not use a Thunderbolt cable.
- Plug the cable into the DFU port of your broken Mac
- Plug the other side to any non-DFU port of your host machine
- Open the Finder on the host machine
- Power up the broken machine in DFU mode
- The broken machine should now appear in the finder. Press the restore button.
- Once the restore is completed, boot your Mac in recovery mode
- Reinstall macOS