Apple technicians use a proprietary tool to generate a challenge file based on your Mac’s unique firmware ID, which they then use to bypass the lock.
Power down, reinstall the RAM, and the EFI password should be cleared. Note: This does work on any Mac where the RAM is soldered to the motherboard. Method 4: Third-Party Hardware Tools unlock efi password top
You must have the original receipt (digital or paper) showing the device’s serial number. Apple technicians use a proprietary tool to generate
If you are using an older Mac (pre-2012) that has removable RAM slots, there is a legendary hardware "glitch" that allows you to reset the EFI. Power off the Mac and remove one of the RAM modules. reinstall the RAM