Mac Performance

How to Start a Mac in Safe Mode

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Do you struggle with starting up your Mac or is it getting slow? Are your user-installed apps malfunctioning? You might need to get your Mac in safe mode to solve these problems.


Macs usually don't freeze or crash thanks to Apple's commitment to seamless interaction between man and machine. But once in a while, you might face some of the problems mentioned above and have to sort them out using safe mode. That's if you hope to continue watching that Netflix show or meet that deadline at work.

In this guide, we’ll cover the following:

Why do you need safe mode on your Mac

Safe mode can be regarded as maintenance for your Mac as it comes with deleting temporary docs and dynamic loader shared caches and checking startup disks. These two activities alone can get your Mac back to its original processing speed. But the most important advantage of safe mode and safe boot so far is the ability to sidetrack potentially troublesome software to create an environment where you can find and rectify these problems.

How to turn on safe mode

The terms “safe mode” and “safe boot” are often interchanged and misunderstood. In reality, we have two different processes that depend on each other. To start your MacBook Pro in safe mode, you need to boot it safely. It's a bit different from the normal booting of your Mac. Here’s how to do it:

  1. Start your computer and wait for the startup chime
  2. Once you hear that chime, press and hold the Shift key till a bar and an Apple logo show up on the screen
  3. Then wait for your laptop to boot into the safe mode environment

How to turn off safe mode

Once you're done with safe mode, and you want to leave, just shut down and restart your Mac normally:

  1. Click the Apple logo and choose to shut down
  2. Then restart your Mac without holding the Shift key

Don't stress if your Mac takes time to shut down. It’s a known fact that staring at the screen slows time and tempts you to obstruct the shutting down process. However, if your Mac doesn’t turn off at all, check out our guide on overcoming Mac shut-down failure.

What safe mode does and doesn't do

It might take some to safely boot your Mac because your system automatically handles specific tasks behind the scenes. But it's okay. These activities assist your system in scanning and clearing problematic files — making safe mode possible.


Some of these activities include:

  • Loading essential kernel extensions since they're necessary to run your Mac
  • Avoidance of specific peripheral kernel extensions
  • Inspecting startup volume and checking startup hard-drive
  • Bypassing third-party installed fonts as they don't count as essential software
  • Deleting dynamic loader, shared cache, and other temporary files slowing down your Mac
  • Disabling all but essential startup items

Safe boot bypasses drives and apps that would have automatically loaded had you conventionally booted your Mac. As a result of these activities, your computer runs on the basic macOS in the limited safe mode environment.


It isn't enough to safe boot your Mac to get into safe mode. You still have a problem that brought you here in the first place. Through maintenance and troubleshooting, you'll find and fix these problems. There are a couple of things you can do in safe mode to solve your Mac's problems. We'll look at two of them.

Restoring files from your Time Machine backup in safe mode

Assuming your Mac is hanging and crashing when you try to use an app, restoring files from your Time Machine backup becomes an option to solve the problem. The thing is, this can only be possible if you have your data backed up on an external drive. If you've got this drive, get it connected to your Mac. You should be able to see it in Finder.

external disk in locations in finder

Open the window for the particular file you want to restore. Go to the Time Machine for this window and find the timeline. Then carefully scroll through the timeline of your chosen file or app till you see the timestamp just before your app starts to misbehave. Select it and click Restore to get it back.

time machine window on recents in finder

If you don't have your files backed up, you may just have to reinstall your system and get your Mac back to its factory settings. The setback with this process is that you lose your existing files and user-installed apps.


But what if you're struggling to install an app that isn't yet on your system? What if your Mac can't boot? Then you might need the second troubleshooting task on this list — disk permissions repair.

Disk permissions repair using safe mode

All of Mac’s files are held secure by disk permissions. It prevents prying eyes and tinkering hands from tampering with your records. If someone wants those files, they will need approval. It's the case with every file and folder on your Mac. On a perfect day, this is an ideal system.


But as with real-life and technology, nothing's perfect all the time. When an app installs and uninstalls, things can get mixed up. Malicious software may alter a file here or there, and soon, your disk permissions misbehave. That's why your Mac is sluggish or crashes when you try to install an app.

The safe mode can save you from malicious apps’ unexpected intrusion, but powerful malware won’t ask for your permission to view your data.


Luckily, through safe mode, you can prevent third-party apps from meddling with your system, giving you time for disk permissions repair. Here's what you do to fix this.


1. Go to Disk Utility

find disk utility in applications folder in finder

2. Select Macintosh HD from the sidebar

find macintosh hd internal drive in disk utility

3. Click on First Aid 

run first aid on internal disk macintosh hd in disk utility

4. Click Verify Disk

5. Click Repair Disk


Let your system take its time to scan for problems after you've clicked Verify Disk. Once you've repaired your disk permissions, you could install your app or boot your Mac normally.


We've just seen a host of things safe mode can do on your Mac computer. What it can't do is solve hardware problems. You'll have to visit an Apple store close by to get it fixed by engineers and technicians.

How to reboot your Mac in safe mode

Do you wonder how to restart a Mac while in safe mode? You'll first have to leave the safe mode environment. Just shut down your Mac as you'll typically do and boot again. This time, don't do anything after that startup chime. Your Mac will start normally this time.

How to know if your Mac is in safe mode

It’s a typical situation when you might be unsure whether it’s in the safe mode. So how to find it out?


Indeed, both regular and safe modes have similar visual environments. But they work not the same way when it comes to what they do. Some of the characteristics of the safe mode environment you may notice include:

  • Inconsistency with the screen display like blinking and tearing
  • A drop in the speed performance of your Mac
  • Peripheral devices like mics or mouse not working
  • The lack of transparency effects because Quartz Extreme system extension is disabled
  • Inability to connect to a Wi-Fi network
  • Your DVD player application not playing movies
  • Video apps like iMovie not working

There are subtle visual differences too, and we'll look at them now. When in safe mode, if you see 'Safe Boot' in your Mac’s login screen menu.

login screen in safe boot - safe boot sign in top right corner

Another way to be sure of your Mac's status is to go to the Apple Menu and check out the About this Mac section. You'll find the Overview button, which leads you to the System Report. Go to Software: there you'll discover Boot Mode, which says Normal or Safe. If you're in safe mode, it'll say Safe.


Safe mode can be a limited environment, but it isn't the typical user interface. It's there to help you find and rectify software problems plaguing your Mac. So let's get to the meat and potatoes, shall we?

What to do if your Mac automatically starts in safe mode

There are several reasons for this malfunction.

Fixing a stuck Shift key

Remember how we discussed pressing the Shift key just after the startup chime to boot your Mac into the safe mode environment? Well, if that key is stuck, your computer will safeboot when you hit the Power button on. Dust can also cause stuck keys. And mind you, you can't always tell if the key is pressed or not. Blow compressed air to dislodge any dirt under the keys — especially the Shift key. Once you've done that, restart your Mac to check if the safe mode problem is gone.

Fixing automatic safe boot with Terminal

Check for any plugged external USB devices and remove them. Then restart your Mac computer. If you still can't access normal mode, let your Mac safeboot to the safe mode environment. Then open Terminal and insert the code below into the Terminal window. This code is the reverse of another code that forces your Mac into safe mode.


sudo nvram boot-args = " "


Now, press Return and insert your admin password when asked. Then boot your Mac again.

Problems with Mac safe mode

When your Mac is starting in safe mode, it runs a checkup of system files and removes caches. If there is an issue with your file system, your computer won't get past this stage in the process. That's when your system hangs or crashes when starting in safe mode. What you need to do is open Terminal and force your Mac to boot in safe and verbose mode. Here is the code you need to copy and paste in the Terminal command line.


sudo nvram boot-args="-v -x"


Now you can boot your Mac and get into a test environment that'll help you find out what's going wrong. Look for the tool in charge of checking out the file system structure. If you can't find it, there's a big chance that you'll have to clear whatever the issue is with the file system structure. It requires reformatting the hard drive. Before you do it, make sure you have backed up your files.

Features that are not available in safe mode

As we discussed earlier, the macOS safe mode is a limited environment used strictly for utilitarian purposes.

  • Your third-party apps won't work
  • You won't be able to use peripherals like mics and some disk drives
  • You won't be able to connect to a Wi-Fi network
  • Other non-essential apps like iMovie won't play

Safe mode can be quite a restrictive operational mode for your Mac, but its strength is in the limitations it provides. Your Mac uses safe boot and safe mode to bypass shortcomings like incorrect startups and software problems that start as soon as you boot your computer.


During this time, your Mac inspects the startup disk and deletes cache. Think of it as cleaning your messy room to find your keys. It's a maintenance and troubleshooting environment to help you find out what's wrong with your computer and fix it.


We hope that with the detailed description of what to do, you'll be able to get in, find and rectify your Mac's problem and get back to watching Netflix, learning stuff on the internet, or meeting the deadline on that project. If you’re still struggling to switch your Mac to safe mode, then just ask our MacKeeper experts for help!


What is Mac safe mode?

Mac safe mode is a limited version of macOS that you can use for troubleshooting. By starting your Mac in safe mode, you can prevent faulty software from interfering with the proper work of your Mac. For example, if your Mac doesn’t boot up, you can start it in the safe mode and address the issue there.


Mac safe mode offers a great opportunity for diagnosing your device. When your Mac doesn’t work properly, observe its performance in the safe mode to narrow down the source of an issue. If the Mac works without a hitch, then hardware is to blame.

How to use safe mode to resolve Mac startup issues?

To resolve Mac startup issues using the safe mode, you just need to shut down your device for 10 seconds and boot it up while holding the Shift key. Then, release the key when the login window appears on your screen. Thus, your Mac will enter the startup mode.


The safe mode helps to resolve Mac startup issues by allowing your device to run in a limited macOS environment. Specifically, the safe mode disables potentially conflicting startup items, deletes temporary files, bypasses peripheral kernel extensions, and checks your startup volume.


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