macOS sandboxes apps but it cannot be as restrictive about which apps are installed on it as iOS is. This means that while it is difficult to install something malicious enough to hijack your Mac, it is nevertheless still possible. Additionally, malicious apps aren’t the only problem a Mac user has to be concerned about. Sometimes, simply installing a poorly made app or tinkering with things you shouldn’t be tinkering with, might render the system unusable. The best way to go about fixing this is to boot macOS in safe mode.
macOS safe mode
macOS has a safe mode like all other operating systems do. Like other safe modes, this mode is restrictive in what is allowed to run on the desktop. Specifically, some third-party apps are disabled, file sharing is disabled, and you’re free to remove apps from your system if you think they’re causing problems.
To boot macOS in safe mode, you need to either shut down and boot your system, or simply restart it. As the system is starting up, tap and hold the Shift key. It’s a good idea to press it right after you tap the power key.
Keep holding the Shift key until you get to the login screen. You will see the Apple logo with the loading animation before that and it will probably take longer to load up the OS than it usually does when you boot to the normal state.
Once you see the login screen, look at the menu bar and it ought to read Safe Mode in red. If you don’t see it, that means you were too late in holding down the Shift key. This is likely to happen if you have a newer Mac model which can boot up faster than older ones. Restart your system and try again.
When you boot to your desktop in Safe mode, you will no longer see the Safe Mode message in the menu bar. You will see it in the menu bar on the login screen if you choose to lock your Mac.
Exit Safe mode
Exiting safe mode on macOS is the same as it is on other desktop operating systems. All you have to do is restart your system. When it’s booting up, don’t press any keys on your Mac until you get to the login screen. Not only will you get to the login screen quicker but the menu bar will also indicate that you’re in normal mode by not showing the Safe Mode message.