Firmware lock - 2015 MBP

[Dwight__SCHRUTE]

I have a 2015 15" MBP. It is a max spec BTO model that still remains in perfect condition. I cleaned the case and applied new thermal paste. I'm going to replace the aging battery, too. It is surprisingly useable in 2025, at least for basic computing work.

I tried to instal Sonoma via OCLP but when I booted via "option" I got a padlock icon. I do not recall ever setting a firmware password. I've read that the only way to break it is to bring it to Apple with a proof of purchase, but I don't have said proof of purchase (it's a decade old!) and I doubt Apple would touch a non-supported item anyways.

Is there any other way to bypass this lock?

 

[Audit13]

Are you the first owner of the MacBook?

I have a mid-2014 13" MacBook Pro and installed Windows 10 for an older relative wanted a Windows laptop just to surf and check email, nothing else. Windows 10 ran fine until they dropped it and Windows would not boot. When I went to reinstall using Internet Recovery, the MacBook had a firmware password as well. I purchased the MacBook directly from Apple and never set a firmware password for any of my Macs or MacBooks. Nothing I tried could get me back in. Never contacted Apple since the MacBook was not worth repairing and reusing.

 

[Bigwaff]

Is there any other way to bypass this lock?

The only other way I've heard of is to reprogram the EFI chip on the logic board.

 

[macsforme]

The only other way I've heard of is to reprogram the EFI chip on the logic board.

This is a viable option. With an “ENIT SAM” connector (I found one for about $80 about a year ago) and an EEPROM programmer like a ch341a, you can extract your firmware image, perform the necessary manipulations, then flash it back. I have done this a few times to downgrade the firmware version.