If you enter the wrong password enough times in Recovery Mode, a "Recovery Assistant" menu may appear in the top menu bar. From there, you can select "Erase Mac," which may allow you to reset the device (though this will delete your data). 3. Older Intel Macs (Pre-2011)
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How to Remove an EFI Firmware Password on a Mac A firmware password (EFI password) provides a high level of security by preventing your Mac from starting up from any device other than your designated startup disk. However, if you forget this password, you can find yourself locked out of essential troubleshooting tools like Recovery Mode or the ability to boot from external drives. remove efi firmware passcode on mac