Follow these steps if your Apple computer won't boot or start to your login screen. Always consider hiring a professional. We are not responsible for loss of data or computer damage when you follow these steps.
If your Mac is stuck on the Apple logo
If you think you've waited long enough to know that your Mac is stuck on this screen, follow these steps.
Some of the fixes below are extreme. Make sure you have a backup and consider hiring a professional such as myself. See my article first on MacBook Pro Keeps Restarting 8 Ways to Fix Random Restarts. Some of the fixes such as resetting NVRAM or PRAM should be done first.
Press and hold the power button on your Mac for up to 10 seconds, until your Mac turns off. (Every Mac has a power button. On notebook computers that have Touch ID, press and hold Touch ID.)
Turn your Mac back on. If the issue persists, press and hold the power button until your Mac turns off. Then unplug all accessories from your Mac, including printers, drives, USB hubs, and other nonessential devices. You could have an issue with one or more of those devices or their cables.
Turn your Mac back on. If the issue persists, press and hold the power button once again until your Mac turns off. Then follow the steps in the section on howow to repair a Mac disk with Disk Utility. It explains how to start up from macOS Recovery so that you can use Disk Utility.
How to repair a Mac disk with Disk Utility
Use the First Aid feature of Disk Utility to find and repair disk errors.
Disk Utility can find and repair errors related to the formatting and directory structure of a Mac disk. Errors can lead to unexpected behavior when using your Mac, and significant errors might even prevent your Mac from starting up completely.
Before proceeding, make sure that you have a current backup of your Mac, in case you need to recover damaged files or Disk Utility finds errors that it can't repair.
Open Disk Utility
In general, you can just open Disk Utility from the Utilities folder of your Applications folder. However, if your Mac doesn't start up all the way, or you want to repair the disk your Mac starts up from, open Disk Utility from macOS Recovery:
Determine whether you're using a Mac with Apple silicon, then follow the appropriate steps:
Apple silicon: Turn on your Mac and continue to press and hold the power button until you see the startup options window. Click the gear icon labeled Options, then click Continue.
Intel processor: Turn on your Mac, then immediately press and hold these two keys until you see an Apple logo or other image: Command (⌘) and R.
You may be asked to select a user you know the password for. Select the user, then click Next and enter their administrator password.
From the utilities window in macOS Recovery, select Disk Utility and click Continue. macOS Recovery options with Disk Utility selected
Select your disk in Disk Utility
Choose View > Show All Devices (if available) from the menu bar or toolbar in Disk Utility.
Disk Utility: Show All Devices
Repair volumes, then containers, then disks
For each disk that you're repairing, start by selecting the last volume on that disk, then click the First Aid button or tab.
Click Run to begin checking the selected volume for errors.
If there is no Run button, click the Repair Disk button instead.
If the button is dimmed and you can't click it, skip this step for the disk, container, or volume you selected.
If you're asked for a password to unlock the disk, enter your administrator password.
After Disk Utility is done checking the volume, select the next item above it in the sidebar, then run First Aid again. Keep moving up the list, running First Aid for each volume on the disk, then each container on the disk, then finally the disk itself.
Disk First Aid: process complete
When you're done, quit Disk Utility. If you used Disk Utility from macOS Recovery, you can now restart your Mac: choose Apple menu > Restart.
If Disk Utility found errors that it can't repair
If Disk Utility found errors that it could not repair, use Disk Utility to erase (format) your disk.
Use Disk Utility to erase an Intel-based Mac
How to erase (format) built-in startup disk of an Intel-based Mac.
These steps do not apply to Mac computers with Apple silicon. If you're using a Mac with Apple silicon, follow the steps to erase a Mac with Apple silicon.
Before erasing your Mac
If using macOS Monterey or later on a Mac with the Apple T2 Security Chip, follow the steps to erase all content and settings instead of these steps.
Make a backup of any files that you want to keep. Erasing your Mac permanently deletes its files.
Use Disk Utility to erase your Mac
Start up from macOS Recovery: Turn on your Mac, then immediately press and hold these two keys until you see an Apple logo or other image: Command (⌘) and R.
If asked, select a user you know the password for, then enter their administrator password.
From the utilities window, select Disk Utility and click Continue.
Select Macintosh HD in the sidebar of Disk Utility. Don't see Macintosh HD? Click the Erase button in the toolbar, then enter the requested details:
Name: Macintosh HD
Format: APFS or Mac OS Extended (Journaled), as recommended by Disk Utility
Click Erase Volume Group. If this button isn't shown, click Erase instead.
Disk Utility window showing Erase volume group confirmation
If asked, enter your Apple ID.
Optional: If you previously used Disk Utility to add internal volumes other than Macintosh HD, you can erase them individually using the same process.
When you're done, quit the Disk Utility to return to the utilities window.
If you want your Mac to start up again from the volume you just you erased, select Reinstall macOS in the utilities window, then click Continue and follow the onscreen instructions. Learn more about reinstalling macOS.
If you don’t see Macintosh HD in Disk Utility
Your built-in startup disk should be the first item listed in the Disk Utility sidebar. It's named Macintosh HD, unless you changed its name. If you don't see it there, choose Apple menu > Shut Down, then unplug all nonessential devices from your Mac and try again.
If your disk doesn't appear in Disk Utility
If Disk Utility can't see your disk, it also can't see any containers or volumes on that disk. In that case, follow these steps:
Shut down your Mac, then unplug all nonessential devices from your Mac. If you're repairing an external drive, make sure that it's connected directly to your Mac using a cable that you know is good. Then turn the drive off, wait 30 seconds, then turn it back on.
If Disk Utility found no errors, reinstall macOS.
Make this a last resort and make sure your files and photos are backed up. Also make sure you know all your passwords. You might want to hire a professional to do this.
If Disk Utility found errors and repaired them, restart your Mac. If the issue returns after restarting, reinstall macOS.
