Mac Does Not Boot into any Options

Unless you previously modified the laptop's security settings to allow booting from an external drive, then most likely it is now too late since there are no active macOS user accounts registered on this Mac now that the internal SSD has been erased (even though recovery is still there...there are no longer any user accounts). So a bootable USB is no longer an option.

That means you must work out the issue with Internet Recovery Mode.

Unfortunately it is very hard to troubleshoot network issues involving Internet Recovery Mode especially using WiFi because there are so many potential issues with a WiFi connection. Try connecting the laptop directly to the router using an Ethernet cable and USB-C to Gigabit Ethernet Adapter for a faster more reliable connection which is easier to troubleshoot.

There is a possibility you will need to try a "Revive" procedure in case there is an issue with the T2 chip or the system firmware which is causing problems with accessing Internet Recovery Mode. If a "Revive" doesn't help, then you will need to try a firmware "Restore" which resets the T2 chip & system firmware like the "Revive", but also erases the internal SSD. If the "Restore" does not push a clean copy of macOS onto the internal SSD, then you will need to boot into Internet Recovery Mode afterwards to reinstall macOS. If you have this laptop connected to the Internet while performing the "Restore" it may push a clean OS onto the internal SSD. I thought on a few Macs that macOS was pushed onto the SSD, but on others I had to use Internet Recovery Mode after the "Restore" firmware procedure.

Revive or restore an Intel-based Mac using Apple Configurator - Apple Support

If all else fails, then you may need to take the laptop to an Apple Store or Apple Authorized Service Provider for assistance in case you have a hardware issue with the laptop.

Beyond these suggestions, there isn't anything you can do if you've tried different physical locations and ISPs.

david_ferguson97 wrote:

Thanks so much for this HWTech! So I managed to sort out the Recovery issue (was indeed related to ISP settings, got a whitelisted connection and that solved the trick with getting into Internet Recovery).

You are lucky, most people would not be able to get a whitelisted connection.

What's happening now is that as soon as recovery loads it goes straight to the Activate Mac page BUT this doesn't ever manage to establish a connection with the Activation Servers - argh!

I wasn't quite sure about the "Activation" part, so a quick search brought me these two posts by @Encryptor5000 (in the same thread) which helps to explain the "Activation", not that it will actually help you here, but more for general information:

Activate mac -- Post#1 - Apple Community

Activate mac -- Post#2 - Apple Community

It's so strange that it then also gives me the option to boot into Target mode but that just returns back to Internet Recovery (think that it's to do with the Target mode probably also not being accessible/disabled)...

With 2018+ models, you must first authenticate with an authorized admin user account on the Mac before being able to do anything. The data on the internal SSD of the 2018+ Macs are hardware encrypted, so you must authenticate to allow access to the encrypted data.

I also tried doing the system revive but the key combinations don't register and the device continues the loop - so I guess that next step is to take it into an iStore :(

It is tricky to get the laptop into DFU Mode. It can take multiple attempts until you get the timing correct. Plus Apple Configurator doesn't necessarily scream that you are successful. All you get is "DFU" showing in a grey box in the center of the Apple Configurator window. Make sure you are also pressing the proper keys since you must use the Right Shift key (the Left Shift won't work), plus the Command + Option keys pressed must be on the left side of the keyboard. You also need to make sure the computer is completely shutdown. The best way to do this is while the laptop is powered on press the Caps Lock key so the LED is lit, then press & hold the TouchID button until the Caps Lock LED goes dark.

Also, make sure you are connecting the USB-C charging cable to the front left USB-C port on the "broken" laptop....no other port will work. Make sure you are using the USB-C charging cable since a Thunderbolt/USB3 cable will not work for this procedure.

Unfortunately it can be tricky & frustrating to achieve DFU Mode. Make sure Apple Configurator is already running & open on the host Mac so you can watch for "DFU" to appear on the center of the app window since there are no other clues as to what the laptop is doing.

Thanks again for the help here, will see what Apple techies say and will post an update here... Fingers crossed!

You may want to ask to watch the Apple tech putting the laptop into DFU Mode.

Please let us know how it all works out.

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That may help !!...