Safe Boot / Safe Mode
- by Jo Woodbridge
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- 03 Feb, 2018
- •
Use safe mode to isolate issues with your Mac
You can use safe mode to help resolve issues that might keep your Mac from completely starting up, or to isolate other issues related to your startup disk.
What is safe mode?
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 your Mac in safe mode does the following:
- Verifies your startup disk and attempts to repair directory issues, if needed
- Loads only required kernel extensions
- Prevents startup items and login items from opening automatically
- Disables user-installed fonts
- Deletes font caches, kernel cache, and other system cache files
If your Mac has an issue that goes away when you start up in safe mode, you might be able to isolate the cause.
Start up in safe mode
To start up in safe mode:
- Start or restart your Mac, then immediately press and hold the Shift key. The Apple logo appears on your display. If you don't see the Apple logo, learn what to do.
- Release the Shift key when you see the login window. If your startup disk is encrypted with FileVault, you might be asked to log in twice: once to unlock the startup disk, and again to log in to the Finder.
To leave safe mode, restart your Mac without pressing any keys during startup.