FileVault can be disabled in the Security system preferences using the FileVault tab, but the firmware password must be disabled using the Firmware Password utility that is available in the Utilities menu in the OS X installer (You can get to this in OS X Lion and later by holding Command-R at startup).Ī second potential issue that prevents Safe Mode from working is if you have a wireless keyboard. To enter Safe Mode, you must first disable these options. If you have Apple's FileVault disk encryption technology enabled, or if you have a firmware password set on your system, then the computer will not boot to Safe Mode. Some security settings in OS X may contribute to the inability to boot to Safe Mode. FileVault in OS X 10.7 'Lion' or later will prevent booting to Safe Mode. The inability to boot into Safe Mode may happen because the system is configured with encryption or other security settings that prevent booting to such modes, because of nuances with how wireless keyboards pass boot arguments to the system, or because of errors in the file system. To get into Safe Mode you simply restart your Mac with the Shift key held however, in some cases this will not work and the computer may simply boot normally or experience a problem and hang without booting at all.

If your Mac is experiencing problems running, one step for determining the problem is to boot the system into Safe Mode, which is a limited environment that only loads Apple-provided software for basic functionality.

Mac startup commands a1278