To perform a Safe Boot, decrypt your startup (boot) volume by disabling FileVault 2. You can enable FileVault 2 again afterwards.
- From the Apple () menu, choose System Preferences.
- From the View menu, choose Security & Privacy.
- Click FileVault.
- Click the lock icon in the lower left-hand corner and enter your admin password.
- Click the "Turn off FileVault" button.
After FileVault 2 has finished decrypting your hard drive, you can restart with a Safe Boot. Enable FileVault 2 again after using Safe Boot, if you wish.