There’s no need to panic if your Mac won’t start. macOS includes some simple fixes that can help get everything right straight away. You don’t need to take your machine to a service center for repair yet. Save yourself time and money by trying to fix it yourself.

We’ll show you how to use features like Disk Utility's First Aid, fsck, and tools built into macOS recovery to revive a Mac that refuses to start.

Before We Begin

These tips are for instances where your Mac refuses to boot. You might see a black screen, you could get an error message, or your computer may hang on the white Apple logo. If your machine is running fine, this troubleshooting guide is not for you.

If you suspect problems with your startup drive due to performance issues or erratic behavior, running First Aid certainly won’t hurt. But first, doesn't it make sense to ask what First Aid actually does?

When your Mac starts up, it performs a quick consistency check to scan the startup disk and to verify the partition scheme (the space where volumes exist) and volume directory structure (which catalogs the stored files and folders).

Launch Disk Utility and click First Aid followed by Run, selecting volumes in the following order:

  1. Macintosh HD - Data
  2. Macintosh HD (assuming you haven’t renamed the startup volume)
  3. Container disk
  4. SSD

If First Aid finds any errors, it’ll attempt to automatically fix them.

run first aid

1. Try Safe Mode

“Safe Mode” provides you a starting point to help you determine whether an issue is caused by software that loads as your Mac starts up or a hardware problem. Booting your Mac in Safe mode verifies your startup disk and repairs directory issues, if needed.

It loads only the bare minimum system extensions, leaving behind third-party kernel extensions and login items while clearing font, kernel, or other system caches. If the issue returns after leaving Safe Mode, you’ll know where to start looking for culprits. To boot into Safe Mode, follow the sequences below

Intel Macs: Turn on or restart your Mac, then immediately press and hold the Shift key. A Mac in Safe Mode shows the words “Safe Boot” in bright red text at the upper corner of the login screen.

safe mode shift login

Apple Silicon Macs: Shut down your Mac. Press and hold the power button (for at least 10 seconds), until your Mac displays the startup options window. Select your startup disk, then press and hold the Shift key. Click Continue in Safe Mode or press Return.

If you’re finding it difficult to find the specific component, try Verbose mode by holding Cmd + V on startup and scan the startup process. Restart into Safe Mode, remove the component, then try again.

Related: A Quick Guide to macOS Boot Modes and Startup Key Combinations

2. Repair Your Disk in macOS Recovery

Every Mac ships with macOS Recovery, which lives on a separate partition on the startup disk. This mode allows you to repair or restore the startup drive, access the Terminal, and reinstall macOS. To boot into macOS recovery, follow the below steps:

Intel Macs: Restart or turn on your Mac, then immediately press and hold Cmd + R. Release the keys when your Mac displays anything on the screen. If you’ve set up a firmware password, you must provide it to access recovery mode.

recovery mode Intel macs shortcut

M1 Macs: Shut down your Mac. Press and hold the power button until you see a prompt that says “Loading startup options.” A set of one or more drives should appear along with a gear icon labeled Options. Select Options, then press Return.

Once you’re in macOS Recovery, launch Disk Utility and proceed to run First Aid as discussed above. If Safe Mode didn’t fix your issue, performing this step should repair your disk and file system, which may not be possible when you use them as a startup drive.

Trouble Booting Into macOS Recovery?

If you have trouble booting into macOS Recovery, perhaps due to problem with your drive, you can start macOS Recovery over the internet (by holding Cmd + Option + R) or from the recovery volume located on an external drive instead.

Again, it depends on the type of Mac you own. In Macs with the M1 chip, there are no restrictions for booting from external volumes since each volume has its own security settings. But in Intel Macs with the T2 chip, it’s necessary to enable “booting from external media.”

3. Use fsck in Single User Mode

If Safe Mode or performing first aid in macOS Recovery didn’t fix your problems, we’ll use fsck (file system consistency check). It’s a popular Unix tool for checking and fixing drive problems. Single-User mode allows you to make changes to shared user resources.

It doesn’t attempt to boot macOS, but simply provides access to Unix command line. To boot into Single-User mode, start your Mac in macOS Recovery and choose Utilities > Terminal. This procedure applies to both Intel and M1 Macs.

For older Macs, press and hold Cmd + S when your computer boots. If you have set a firmware password, then Single-User mode is not available to you. When you’re in the Terminal, type the following and hit Return:

        /sbin/fsck -fy
    

(Wherein “f” means that it'll force the utility to check the drive file system, and “y” means it'll automatically confirm the actions of fsck command.)

Depending on the size of your volume, it may take a while for this process to complete. Repeat this commmand until you see the message “The volume Macintosh HD appears to be OK.”

Then, run:

        /sbin/mount -uw
    

This will mount the startup volume as a read-and-write file system. Once you’re done, run the exit command to start up the Mac.

Still Can’t Boot Your Mac?

If your Mac still won’t boot after running First Aid and fsck, you may have some serious problems with your drive. At this stage, it’s advisable to back up your files and run Apple Diagnostics to see if there are any obvious problems.

Target Disk Mode

Since this feature is built into Intel-based Macs, you can use it to recover data even if the installed macOS volume is corrupted. Here’s a quick on how to recover files with Target Disk Mode.

target disk mode

Note: M1 Macs use Share Disk instead of Target Disk Mode. To use this, restart in macOS Recovery, then choose Utilities > Share Disk. Select your startup disk, and click Start Sharing. Connect your Mac to another Mac via USB cable and you’ll see the shared disk in Finder sidebar.

Create an Image of the Disk

You can even create an image of the faulty drive, for which you’ll need to connect a spare external drive that’s at least as big as the startup disk. Boot your Mac into macOS Recovery, then launch Disk Utility. From the menu bar, choose File > New Image > Image from “Macintosh HD”. Specify your external drive and start the process.

This may take a while, and there’s no guarnatee that the process will be a success. On completion, it’ll create a DMG file of your old drive that you can mount and sort through at your convenience.

write external drive

Copy Your Files Manually

You have the option to manually copy files. Start your Mac in macOS Recovery and launch Terminal. Then connect the external drive you want to use as a destination for your files.

Run the cp -r command. For example, cp -r /Volumes/Macintosh\ HD/Users/[username]/Documents /Volumes/Backup/**.

Here, cp is the copy command, and -r runs this command recursively. That means it’ll copy all directories within the directory you specify, then the directories within them, and so on.

The first path is the location of the files. Note the backslash (\) in the path name, which you use to specify locations that have spaces in their name. The second path is the location of your external drive, which will always be in /Volumes/ with whatever label you’ve given (in this example, the drive is called Backup).

The Importance of Backing Up Your Mac

Hopefully, you’re able to recover your drive or any important files you may need. Even with a successful recovery, and the many tools we've discussed at your disposal, there’s nothing quite like the peace of mind a recent backup provides.

You don’t even have to use Time Machine to keep your Mac safe. Why not try one of the many other Mac backup tools available to backup your Mac.