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Resolved Drive wiped now can’t install MacOS

Apple fanboy

Apple fanboy

macrumors Ivy Bridge
Original poster
Feb 21, 2012
57,424
56,601
Behind the Lens, UK
So my 2018 Mac mini decided to act up this week. I thought I’d upgrade to Sonoma.
Big mistake. Unfortunately it got stuck in a loop trying to download then would crash.
I decided to reinstall from my Time Machine back up. That just lead to more issues. Ended up with Ventura (but not very stable). Tried to upgrade from there.
Yup you guessed it back to getting stuck in the loop.

So I erased my SSD to see if that would help. Still not able to get running.
Lastly I created an installer for Ventura which I did on my work Mac.

Pretty sure that is all good (on an SD card created with Disk creator).

However when I start using option and select the drive it tries to download Mojave from the internet and gets stuck in the loop.

Pretty sure I have the T2 chip preventing it from booting from an external. But I can no longer change that setting as I have no installed user.

Any suggestions for the next steps to try?
 
You should be able to reinstall macOS from Recovery, by following these steps (make sure to use the steps for Intel Macs):

How to reinstall macOS - Apple Support

You can use macOS Recovery, your computer's built-in recovery system, to reinstall the Mac operating system. Reinstalling macOS doesn't remove your personal data.
support.apple.com support.apple.com
 
Grumpus said:
I would try booting with Option-Command-R or Option-Shift-Command-R to attempt an internet recovery. If that fails, you're probably just stuck given the stupid T2 defaults which prevent booting from external media. In that case, I would call Apple Support.
Click to expand...
I’ve tried the internet recovery a few times. That’s the infinite loop I’m stuck in I mentioned.
 
chabig said:
You should be able to reinstall macOS from Recovery, by following these steps (make sure to use the steps for Intel Macs):

How to reinstall macOS - Apple Support

You can use macOS Recovery, your computer's built-in recovery system, to reinstall the Mac operating system. Reinstalling macOS doesn't remove your personal data.
support.apple.com support.apple.com
Click to expand...
The in built recovery got deleted. It wasn’t working anyway.

Currently I’m trying to run first aid on my Time Machine external. Although it downloaded the latest MacOS from there, it then tried to head to the internet to download Mac OS and I was back in that darn loop.

Not sure Apple support will assist on a 6 year old machine.
 
MarkC426 said:
Is this any help...?

About Startup Security Utility on a Mac with the Apple T2 Security Chip – Apple Support (UK)

Use Startup Security Utility to make sure your Mac always starts up from your designated startup disk and always from a legitimate, trusted operating system.
support.apple.com support.apple.com
Click to expand...
Thanks. I did this originally when trying to boot from an external. That failed.
But as I deleted the drive I no longer have a user on there to enter the password required to make changes.

Looks like my first aid for the external 4TB Time Machine is going to take ages. I’ll see where I am in the morning.
 
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Apple fanboy said:
Not sure Apple support will assist on a 6 year old machine.
Click to expand...
It costs nothing to call and ask.

I have a 2019 T2-equipped MBA. Since the T2 firmware was updated during an install of Big Sur, internet recovery does not work at all, the result always being a lengthy download followed by error -1008F. I suspect you'll run into the same thing, but it's still worth trying.

When I spoke to Apple Support about this, way back in 2021, the advice was to take the laptop to an Apple Store. Presumably they can reprogram the T2. Unfortunately, the only Apple Store in my state was closed due to the pandemic at the time, so that never got done. The good news for me is that I had previously used the startup security utility to allow booting from external drives. I wish I could say that was foresight on my part, but it was more a matter of luck.
 
Grumpus said:
It costs nothing to call and ask.

I have a 2019 T2-equipped MBA. Since the T2 firmware was updated during an install of Big Sur, internet recovery does not work at all, the result always being a lengthy download followed by error -1008F. I suspect you'll run into the same thing, but it's still worth trying.

When I spoke to Apple Support about this, way back in 2021, the advice was to take the laptop to an Apple Store. Presumably they can reprogram the T2. Unfortunately, the only Apple Store in my state was closed due to the pandemic at the time, so that never got done. The good news for me is that I had previously used the startup security utility to allow booting from external drives. I wish I could say that was foresight on my part, but it was more a matter of luck.
Click to expand...
If allowed it as well, but when I deleted the drive I suspect this was factory reset to don’t allow. I mean I’m only guessing that’s the issue. I’ll try Apple Support tomorrow. If I have to take it in, it’s only around an hours drive. But I’m not sure what the cost would be.
 
If you changed the startup security settings, I don't think an attempted install would change them (one would hope, anyway). You might want to try again with a USB drive instead of the SD card.
 
So spent the best part of 12 hours restoring from Time Machine. All looked good until it got to the end though. Then a message saying it couldn’t restore files. But I know it must have done some it.
Now it’s offering me Catalina as the OS to restore. Before it was Mojave. I’ll see where that gets me in 18 minutes or so….
 
So no joy. I spoke to Apple. Apparently my Mac needs a firmware update. Have an appointment at the Genius Bar tomorrow after work.

Fingers crossed. I’ll let you know how it goes.
 
Do you have ANOTHER Mac at home, by any chance?
If so, WHAT Mac, what year made, and what OS is running?
 
Something you could try:

Use your work MBP.

Download "Mist" from here:
github.com

GitHub - ninxsoft/Mist: A Mac utility that automatically downloads macOS Firmwares / Installers.

A Mac utility that automatically downloads macOS Firmwares / Installers. - ninxsoft/Mist
github.com github.com
(go to "latest" and download the dmg file)
It's free and a very useful utility.

Mist can download Mac OS installers AND create a bootable flash drive in one step.
It's VERY easy to use.
Just try it.

Download the Sonoma installer. I think you will need a 32gb flash drive.
16gb -might- work, don't know.

Take the installer to the 2018 Mini.
(I'm typing this on my own 2018 Mini, running Sonoma from an external SSD).

Make sure the power is all the way off. Pull the plug if you have too.

Connect the flashdrive.

Hold down the option key (DON'T LET GO OF IT) and press the power on button.
KEEP HOLDING OPTION DOWN.

Can you get to the startup manager?

If so, select the USB flashdrive with the pointer or arrow keys and hit return.

Will the flashdrive boot?
Can you get to installer?

OPTION 1

At this point, you can try running the installer "over" the existing (failed) OS on the drive (assuming there is one).
It may or may not work.

OPTION 2

This is "the better way to go".
QUIT the installer if the flashdrive boots to the installer app.
Open disk utility instead.

VERY IMPORTANT STEP:
In disk utility, go to the view menu and choose "show all devices".
You can't see the Mini's internal SSD until you do this!

Now, look at the list on the left.
You should now be able to see the Mini's internal SSD (it should be the "top line").
Click on this, and then click "erase".
Erase to APFS, GUID partition format.

Quit disk utility and open the OS installer.
Start clicking through.
The Mac will reboot one or more times, and the screen will go dark for a minute or more with no other indication of activity.

When done, you should see the initial setup screen "choose your language".
If you have a backup, CONNECT IT NOW.

Start clicking through.
Setup assistant will ask if you wish to migrate data.
If so, point the way for SA (to the backup), and give it time to digest things.
SA will present you with a list of stuff to migrate.
I suggest you just "migrate it all".

Good luck.
I suggest you PRINT OUT this reply, and CHECK OFF each step I've outlined.
 
Thanks for all your help guys.
I took it to the Apple Store after a phone call. They ended up doing a revive (as suggested above ) and installed the latest MacOS for me.
All free of charge. Can’t really argue with that. Couldn’t imagine Dell or Lenovo fixing a 6 year old computer for nothing.

I was advised to do a clean install rather than restore from my Time Machine.

I’ve ordered a new 4TB SSD usb c drive to back up in future on. Should really speed up the process!
 
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