How to Set the Firmware Password on a Mac
- 1). Insert your Mac OS X installation DVD and restart the system. Press and hold the "C" key while the system restarts until you see the Apple logo. Wait for the installer to load.
- 2). Select your language and click "Continue." Open the "Utilities" menu and click the "Firmware Password Utility" option. Click the "Require password to start this computer from another source" check box.
- 3). Enter the password you want to assign in the field provided. This is not the same as your user password, so enter a separate password for the open firmware protection. Click "OK."
- 4). Click the "Quit" option from the "Firmware Password Utility" menu. Click the "Quit Installer" option in the "Installer" menu to restart in Mac OS X without reinstalling.
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