This is tip that we are sharing with you who own an old Apple Mac Book who has forgotten firmware password on older Apple iMac for models (2009 or older).
If your Apple iMac powers on and shows a padlock icon asking for password, it has firmware password lock on it. You can remove this firmware password by following this simple instructions:
- Access the RAM slots at the bottom of the iMac
- Remove one RAM stick to make the hardware configuration different
- Power on your iMac, and do a PRAM reset by immediately press and hold Option-Command-P-R
- You should hear a boot Apple chime within a few seconds
- Keep holding those same 4 keys, until you hear the boot chime 3 more times
- Release those keys and turn off your iMac
- Reinstall the RAM stick that you removed earlier
- Boot the computer normally and the firmware password should have been removed!
Enjoy your old much loved Apple iMac!
Apple Suggestion:
How to turn on a firmware password
- Start up from macOS Recovery.
- When the utilities window appears, click Utilities in the menu bar, then choose Startup Security Utility or Firmware Password Utility.
- Click Turn On Firmware Password.
- Enter a firmware password in the fields provided, then click Set Password. Remember this password.
- Quit the utility, then choose Apple menu > Restart.
Your Mac asks for the firmware password only when attempting to start up from a storage device other than the one selected in Startup Disk preferences, or when starting up from macOS Recovery. Enter the firmware password when you see the lock and password field:
How to turn off a firmware password
- Start up from macOS Recovery. During startup, you will be prompted to enter the firmware password.
- When the utilities window appears, click Utilities in the menu bar, then choose Startup Security Utility or Firmware Password Utility.
- Click Turn Off Firmware Password.
- Enter the firmware password again when prompted.
- Quit the utility, then choose Apple menu > Restart.
If you forgot your firmware password
If you can’t remember your firmware password, schedule an in-person service appointment with an Apple Store or Apple Authorized Service Provider. Bring your Mac to the appointment, and bring your original receipt or invoice as proof of purchase.
https://support.apple.com/en-us/HT204156
