How to kill mac - Downgrade Catalina to Mojave

Nope, you're lucky to even have anything different of that 9000F error, I couldn't get rid of it no matter what combination of keys I hold.

The solution is :

1-Another Mac PC with OSX Catalina Beta

2- Or go to https://developer.apple.com/account/ and upgrade to another mac to Catalina Beta

3-From this OSX you can download the .app of catalina Beta

4-Create USB with the command in this web

5-http: //osxdaily.com/2019/06/06/make-macos-catalina-beta-usb-boot-install-drive/

6-Start the PC with option

7-Install from the USB

The solution is :

1-Another Mac PC with OSX Catalina Beta

2- Or go to https://developer.apple.com/account/ and upgrade to another mac to Catalina Beta

3-From this OSX you can download the .app of catalina Beta

4-Create USB with the command in this web

5-http: //osxdaily.com/2019/06/06/make-macos-catalina-beta-usb-boot-install-drive/

6-Start the PC with option

7-Install from the USB

The solution is :

1-Another Mac PC with OSX Catalina Beta

2- Or go to https://developer.apple.com/account/ and upgrade to another mac to Catalina Beta

3-From this OSX you can download the .app of catalina Beta

4-Create USB with the command in this web

5-http: //osxdaily.com/2019/06/06/make-macos-catalina-beta-usb-boot-install-drive/

6-Start the PC with option

7-Install from the USB

I got the 9000F error when trying a cmd option shift R Mojave downgrade from Catalina beta as well..

To get rid of the error, I connected the MacBook Pro with T2 to a wired Ethernet connection via a USB dongle. That allowed me to use Disk Utility and enter enough passwords to erase the SSD during a command R recovery mode reboot. That then allowed me to recover factory Mojave after another cmd option shift R recovery mode reboot.

The key, after hours of trying, was to use a wired network connection (to Apple servers) instead of WiFi.

For whoever reads this, take it to an apple store and set it next to a display macbook or a place where you can entertain yourself while this process is happening. It will take a while . When you're there, open your laptop and hold "option, command, R" on the keyboard and turn it on. You will enter internet recovery mode. Connect it to the apple store network. It may fail once or twice but I kept trying and it eventually worked. I came in to get it inspected but the wanted me to wait 3 hours because they wanted to replace the logic board. That sounded expensive to me so I just did the internet recovery there by myself. Im running MacOS Catalina. DO NOT get your macbook inspected without trying this method first. It might work for you. I tried this at home and nothing would work. My WiFi connection is stable but it seems that apples in store wifi is much more stable so i recommend trying it in one.

marioorellana's process is pretty much what worked for me.

Yesterday, I spent a couple of hours with apple supprt at the store. They had managed to wipe my drive, which I wanted done, and were in the process of restoring Catalina as we couldn't get it operational with any other OS. It was taking too long and I had to go. When I tried to resume the process at my house it would not work.

This morning I saw Mario's post and I realized my problem might be me trying to use WiFi (Thank you, Mario!). I plugged in to my ethernet and tried a few key combinations. I'm sure it was just the repitition that worked and not the specific combo. OPT + CMD + R is was is what I used. But I tried each of them a few times before it worked. Just be patient.

Also, I selected fresh install of Catalina and after it was all up and running I used the Migration Assistant to do a complete restore from a Time Machine backup from a USB C SSD.

Confirmed for me too, i had the same problem, after many try it worked, with the wifi.

Be patient and repete the process until it work !

I'm in a new place now, by which I mean my MBP is no longer stuck on "26 minutes remaining" and now says "Estimating time remaining...". Should I just wait several more hours?

All - I have the fix - confirmed with two rebuilds.

All you have to do is reset the PRAM twice. Then it will rebuild from either WiFi or Ethernet.

I did this after visiting an Apple Store - then again tried at home.

Apparently its the machine remebering the last OSX.

This was on a Macbook Pro 2018.

After PRAM reset - then Option,Command R.

The timer should show approx 14 mins (If it shows 5 or less it fails to 9000F).

Hope this helps you.

I can confirm this works on my 2018 MacBook Pro with touchbar.

Problem: Catalina beta 5 (File Vault enabled, did not allow booting from external drive) -> Recovery Mode -> Wiped main SSD -> tried using a Mojave USB to reinstall MacOS Mojave, but the system wouldn't boot. It kept reverting to the Internet Recovery. Option-Command-R and Shift-Option-Command-R (both on WiFi connectivity) presented error 1008F after 5-10 minutes.

At this point, nothing worked. I didn't even care about downgrading... I just wanted to boot into SOMETHING.

Solution: Shutdown, power on, immediately after powering on holding command-option-p-r until the Apple logo disappeared and reappeared. After it reappeared, I shut down the computer manually and repeated the entire process again (reset PRAM twice). Shutdown again. On the next restart, I held down option-command-R hoping the result would be different, and it was! No error 1008. Although AndyMck mentions that the time should show ~14 minutes, mine showed 6 minutes. It launched into recovery where I reinstalled MacOS (in this case, Catalina beta 5).

*Whew*

My take on it:

If Catalina Beta is installed on T2 equiped Macbook Pro then your T2 running 4.0 Beta version.

Do (!!!) NOT (!!!) try to boot in DFU mode to wipe everything and get back to Mojave. Freaking Configurator 2 (used 2.9 and 2.10 Beta) always trying to downgrade T2 firmware to version 3.6 and it will BRICK the laptop. After first try it will boot in Recovery mode (not DFU) and you will be bringing the laptop to Apple Store for repair. Tried on 2 Macbook Pro's 15 2018.

This is what worked for me. Months ago I installed Catalina b2 in its own apfs container allowing for a Mojave/Catalina dual boot and later deleted it. I then reset the SMC and PRAM due to unrelated issues which re-enabled SIP and no booting from an external drive. I wanted to do a clean reinstall of Mojave but couldn’t boot from usb and couldn’t access recovery. I was getting error 9000F. I removed my MBP from my iCloud account but still got 9000F. Ended up resetting the PRAM twice and was greeted with macos recovery to install Catalina beta.

Confirm for error 1008f plugged into ethernet work for me to load macos recovery to install Catalina beta.