If you see a lock icon, try pressing the Return key three times. On some older systems, this will display a password hint left by the previous owner. If you purchased the device used, contacting the seller is the first and most critical step.
Report: EFI/Firmware Password Unlock Procedures This report outlines the standard and advanced methods for unlocking or removing an EFI (Extensible Firmware Interface) password on Apple Mac computers. An EFI password—also known as a —is a low-level security measure that prevents a Mac from starting up from any device other than the designated startup disk. 1. Official Recovery Methods efi password unlock
If you have your , the most reliable way to unlock your Mac is through official channels. If you see a lock icon, try pressing