Release them and the Mac should boot as normal, though now its PRAM data will have been reset. Keep the keys depressed until you hear a second chime. Power up your Mac and hold these keys as soon as you hear the startup chime. Graphics and system performance will be slower. Launches a Mac in Safe Boot mode, it will check the integrity of your startup volume and will launch with the minimum OS X extensions it needs, no user fonts, startup or login items. Startup from a bootable CD, DVD or USB drive (or N to launch from a network server, if available). Hold down these keys to access critical help. You can also run Disk Utility in normal mode.Įnter Disk Recovery mode (Command-R) to run Disk Utility to Verify and Repair your Disk, or to reinstall the OS. Launch Disk Utility in this mode and Fix Permissions on your drive.
Still having problems? Restart the Mac holding down Command-R to enter Disk Recovery mode.
