Mac T2 after update(There was an error activating your device)

[medinfo]

Macbook Pro 2019 T2
iCloud OFF
MDM unlocked by changing Serial Number
worked fine but after latest update see (There was an error activating your device. Please try again).
Erased and boot in internet recovery, same error.
changed to original serial number (iCloud OFF & MDM ON), same error.
tested with others serial number, same error.
tested (CMD+R), (Option+CMD+R), (Shift+Option+CMD+R), same error
Revived and restored by Apple Configurator and same error.

Any help ?

[anhbanxoi]

Change the serial to the original SN then activate again. (Try reset NVRAM/PRAM by pressing Option + Command + P + R before activate)

[medinfo]

Change the serial to the original SN then activate again. (Try reset NVRAM/PRAM by pressing Option + Command + P + R before activate)

Changed the serial to the original and already reset nvra/pram same error !

[m041633n]

It's on lost or stolen mode I think! Check serial on icloud clean status servers Luke gsm servers¡

[medinfo]

It's on lost or stolen mode I think! Check serial on icloud clean status servers Luke gsm servers¡

Already checked with full GSX Report, Clean and off !

[curiositymaster]

I think Apple found a way to patch our serial number change method of removing MDM. I also did a serial number swap (to remove MDM) and boom, the Mac is now icloud locked (with the new serial number). It seems Apple now revalidates the new serial number if it is linked to pre-existing FMI, which is now being triggered to lock the device on the new bridgeOS update.

[curiositymaster]

For now, I'd advise everyone to pend all Serial swap (unless you're sure the new SN is iCloud free) until we find a fix.

[medinfo]

For now, I'd advise everyone to pend all Serial swap (unless you're sure the new SN is iCloud free) until we find a fix.

but i changed the serial number with others sn icloud off and mdm off, and same error, i know that the new bridgeOS or the new update it's the problem

[curiositymaster]

but i changed the serial number with others sn icloud off and mdm off, and same error, i know that the new bridgeOS or the new update it's the problem

it's the new bridgeOS.

[medinfo]

it's the new bridgeOS.

Any solution ?

[curiositymaster]

Any solution ?

Don't upgrade BridgeOS

[shlomim412]

did you manage to sort this out? could be a bad wifi connection?
worth to try with ethernet cable connected...

[kevingill]

If you're keep the MacBook, it might be worth trying one of the paid bypass services. That should skip the activation page.

[medinfo]

did you manage to sort this out? could be a bad wifi connection?
worth to try with ethernet cable connected...

tested with ethernet same

[medinfo]

If you're keep the MacBook, it might be worth trying one of the paid bypass services. That should skip the activation page.

maybe need the original serial number and maybe the the back cover its not original

[pehol193]

Usually i change one letter in SN. It is locked now? I have to unlock MDM from A2251 Macbook pro.

[TechSplendid]

Hi All,
Hope everyone is doing well. Do I understand correctly that an MDM unlock for T2 machines is no longer possible because of a BridgeOS update?
I was just about to learn this but if it is no longer possible then there is no point :-)

Thanks in advance!

[anhbanxoi]

Hi All,
Hope everyone is doing well. Do I understand correctly that an MDM unlock for T2 machines is no longer possible because of a BridgeOS update?
I was just about to learn this but if it is no longer possible then there is no point :-)

Thanks in advance!

Still possible. Just change your SN

[TechSplendid]

Hi anhbanxoi,

Thank you!!! And what I understood is that you do have to use an existing serial right? Does that have to be a serial from the same model or can it be a serial from another (older) model for example? What I am afraid of is that if you use a serial of an existing model and it is later linked to an icloud that the other also gets an icloud. Or is that not the case?

Thanks again!

[anhbanxoi]

Hi anhbanxoi,

Thank you!!! And what I understood is that you do have to use an existing serial right? Does that have to be a serial from the same model or can it be a serial from another (older) model for example? What I am afraid of is that if you use a serial of an existing model and it is later linked to an icloud that the other also gets an icloud. Or is that not the case?

Thanks again!

You can use any other sn with no MDM even it's currently icloud locked.