When the login screen is shown, the upper right-hand corner will display the words Safe Boot. If the shift key is depressed before the chime occurs, the system will ignore the shift key signal and continue to boot normally.īecause safe mode drops you to the login screen or the desktop, it can sometimes be difficult to tell if you’re actually in safe mode. If you’re using a Bluetooth wireless keyboard, don’t press the shift key until you hear the startup chime. Keep the shift key depressed until you see the login window or the desktop. Start up your Mac while holding down the shift key. (One of the clues that you’ve started in Safe Mode is the phrase “Safe Boot” in the top right corner when at the login prompt.) It disables all startup and login items from being loaded by the system. It deletes all font caches, kernel caches, and system caches. Safe mode allows only system fonts that are provided with the operating system to load all other fonts are disabled. This will prevent third-party kernel extensions from affecting the startup process, and from being available to use once safe mode drops you into the desktop. Safe mode only allows the most basic system kernel extensions to be loaded. Unlike Disk Utility, which can’t repair the startup drive directly, Safe Mode can perform both a verify and a repair of the startup drive’s directory structure. Safe mode uses a process similar to Disk Utility’s First Aid to verify and repair your startup drive. It will also disable some system components, and if it successfully completes the checks, it will finish by bringing you to the standard desktop, though with certain functions disabled. When you invoke safe mode, your Mac will restart and perform various troubleshooting checks on your Mac’s system, hardware, and startup drive. Safe mode allows you to troubleshoot problems you may be having in starting up your Mac, working with specific apps, or system-wide issues. Up first is safe mode, one of the easiest ways to isolate and fix many Mac problems. (Starting up in Safe Mode can take a bit longer than normal as your Mac runs a number of system checks.) In this Rocket Yard Guide, we’re going to show you how to use each mode to help troubleshoot Mac problems you may be experiencing.

The two modes are distinctly different, with safe mode being a more automated approach to fixing Mac issues, and single-user mode being more akin to the Mac’s Terminal app, giving those familiar with UNIX the ability to manually run various troubleshooting utilities and commands.

They’re often used to troubleshoot issues a Mac may be experiencing or to assist in isolating and repairing some common issues that can keep a Mac from starting up correctly, or that make it act strangely when it’s in use. Safe mode and single-user mode are two of the special start-up modes that your Mac can be powered up to.

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