https://jeltsch.org/en/tags/open-firmware/Recent content in Open Firmware on Michael’s DomainHugoen-usCopyright © 2002 - 2026 Michael Jeltsch.Fri, 24 Jul 2026 00:18:18 +0300https://jeltsch.org/en/the_bios_password_of_macintosh_computers_open_firmware/Wed, 04 Apr 2007 00:00:00 +0000https://jeltsch.org/en/the_bios_password_of_macintosh_computers_open_firmware/<p>Macs don&rsquo;t have a BIOS. They have something called Open Firmware instead. So the BIOS password is called Open Firmware password. You boot into Open Firmware by pressing the command (=apple), option, O and F keys simultaneously during system boot. To set the password type <code>password</code> To enable the protection type <code>setenv security-mode full</code> An then reboot by typing <code>reset-all</code> Apart from the full security mode you can also set &ldquo;none&rdquo; (= don&rsquo;t ask password during boot) and &ldquo;command&rdquo; (=gives you only limited access to Open Firmware without the password. The Open Firmeware password can be removed by changing the amount of RAM and three times zapping the PRAM. More detailed information is <a href="http://www.securemac.com/openfirmwarepasswordprotection.php" target="_blank" rel="noopener noreferrer nofollow">available&nbsp; <svg class="svg-inline--fa fas fa-up-right-from-square fa-2xs" fill="currentColor" aria-hidden="true" role="img" viewBox="0 0 512 512" overflow="visible"><use href="#fas-up-right-from-square"></use></svg></a> .</p>