? What is “Safe Mode” on MAC OS

Dears

? What is “Safe Mode” on MAC OS

 

Safe Mode (sometimes called Safe Boot) is a way to start up your Mac so that it performs certain checks, and prevents some software from automatically loading or opening. 

      Starting up in Safe Mode does several things:

v  It verifies your startup disk, and attempts to repair directory issues if needed.

v  Only required kernel extensions are loaded.

v  All user installed fonts are disabled while you are in Safe Mode.

v  Startup Items and Login Items are not opened during startup and login on OS X v10.4 or later.

v  In OS X 10.4 and later, font caches that are stored in /Library/Caches/com.apple.ATS/uid/ are moved to the Trash (where uid is a user ID number).

v  In OS X v10.3.9 or earlier, Safe Mode opens only Apple-installed startup items. These items are usually located in /Library/StartupItems. These items are different from user-selected account login items.

Together, these changes can help resolve or isolate certain issues on your startup disk.

Starting up in Safe Mode

 

Follow these steps to start up into Safe Mode.

v  Be sure your Mac is shut down.

v  Press the power button.

v  Immediately after you hear the startup sound, press and hold the Shift key. The Shift key should be pressed as soon as possible after startup, but not before the startup sound.

v  Release the Shift key when you see the Apple logo appear on the screen.

After the Apple logo appears, it may take longer than usual to reach the login screen. This is because your computer is performing a directory check as part of Safe Mode.

To leave Safe Mode, restart your computer without pressing any keys during startup.

Starting in Safe Mode without a keyboard

If you don’t have a keyboard available to start in Safe Mode but you have remote access to your computer, you can configure the computer to startup in Safe Mode using the command line.

v  Access the command line by either opening Terminal remotely, or by logging into the computer using SSH.

v  Use the following Terminal command:

1. sudo nvram boot-args=”-x”

If you want to start in Verbose mode as well, use

sudo nvram boot-args=”-x -v”

instead.

v  After using Safe Mode, use this Terminal command to return to a normal startup:

1. sudo nvram boot-args=””

Regards