Modern versions of Mac OS no longer need to fix disk permissions. However, this is not the only problem that can occur with the disk or file system. Mac OS has a variety of tools for fixing disk and file system errors.
These options work like chkdsk On Windows, to check and fix disk and file system errors. You can perform a scan from within Mac OS, but sometimes it may be necessary to use recovery mode to fix problems. In the worst case scenario, you may have to run commands fsck manually from Terminal In single user mode.
So don’t panic if your Mac won’t start. Ignore the agonizing feeling that it will take a long time to fix your computer. macOS includes some simple fixes that can help get everything working right away.
You do not need to take your device to service center for repair. Save yourself time and money by trying to fix it yourself. If you backup regularly with Time Machine, you won’t lose much.
Let’s take a look at how to revive a Mac that refuses to start up.
Before we start
These tips are for situations where your Mac refuses to turn on. You may see a black screen, you may get an error message, or your computer may stop booting at the Apple logo. If your device is working fine, then this troubleshooting guide is not for you.
However, you can run First Aid on your drive at any time on your Mac. If you suspect startup drive issues due to performance issues or erratic behavior, turning on First Aid certainly won’t hurt.
to turn on First Aid On the startup volume, run Disk Utility and select Macintosh HD (Assuming you haven’t renamed your startup volume). Click “First Aid” Then “employmentTo check the disk for problems and try to fix them.
1. Try Safe Mode
By trying to boot into safe mode, macOS checks and repairs any errors it finds on the disk. Safe mode boots your operating system with only the minimum options it needs to work.
Third-party kernel extensions will not run, login items will be skipped, and some caching is eliminated. Simply by booting into safe mode, you will scan for problems and get rid of trash that might be causing them.
To boot into Safe Mode: Turn off the computer, then press and hold the . key
Shift while the computer is booting. If your computer hangs at boot up, shut it down by holding the power button until the device turns off (about 10 seconds) first.
If your computer boots properly, try restarting and booting as normal. If the computer turns off again, try using Verbose Mode by pressing
Cmd + V At startup and check to see if add
kernel specific cause of the problem. You can then reboot to safe mode, remove the extension that is causing the problem, and try again.
2. Recovery Mode and First Aid
If safe mode doesn’t solve your problem, recovery mode is your next best bet. Every Mac comes with Recovery Mode, which lives on a separate partition on your startup disk. This mode allows you to repair/restore the drive, access Terminal, and reinstall macOS.
To boot into recovery mode: Turn off the computer, then press and hold
Cmd + R while the computer is booting up.
If you are having trouble booting into recovery mode, possibly due to a drive problem, you can start recovery mode from the internet by pressing
Cmd + Option + R Instead of that. Keep in mind that this requires an internet connection and will take longer, since macOS needs to download the image first.
Once you start in recovery mode, you will see a few options. turn on Disk Utility Then isolate the drive that’s causing the problems—it might have been named Macintosh HD. Select it from the list on the left, then tap First Aid followed by “run”.
3. Use fsck in single user mode
File System Consistency Check (or fsck for short) is an old Unix tool for checking and repairing drive problems.
Depending on the size of the volume, the type of drive you have installed and the possible problem, it may take
fsck Some time to complete the examination. Patience is important here if you want to repair your drive this way.
Gonna be a bad weekend, as this is not what a Mac is supposed to look like during boot. Time for some “fsck -fy” action, and prayers… pic.twitter.com/tWAOFaLlc7
— Blaine Chronik (@BlaineChronik) February 23, 2018
to turn on
fsck , you will need to boot into single user mode. This boot mode allows you to make changes to shared user resources. Single user mode does not attempt to boot macOS; It only provides access to the Unix command line.
To boot into single user mode: Turn off the computer, then press and hold
Cmd + S when you turn it on. You will soon see a command line prompt. You can write
fsck -fy to turn on
note: If you encrypted your drive, you will need to select the relevant user account and enter the password to decrypt it. If you have set up a firmware password that is set on your Mac, the single user mode will not be available to you.
It is important to wait for the end
fsck before restarting the computer again. If you interrupt the process while making changes to the drive, you may incur data loss. When the process is finished, you will see one of the following messages:
** The volume Macintosh HD could not be repaired. *****The volume was modified *****
If you see this message, you must run
fsck -fy once again. There is no harm in trying a few times, as the process makes changes to your drive with each scan.
** The volume Macintosh HD was repaired successfully. *****The volume was modified *****
This is a more encouraging message, but you haven’t yet done what you’re looking for. You have to run
fsck -fy once again.
** The volume Macintosh HD appears to be OK.
This is what you want to see. fsck checked the drive and had to not make any changes.
When you get this message, it’s time to restart your Mac by running the command
Still can’t turn on your Mac?
If your Mac is still unable to boot after booting First Aid And fsck , you may encounter some serious problems with the drive. At this point, it is advisable to backup your files and run Apple Diagnostics to see if there are any obvious problems.
If you really want to try to solve the problem on your own, you will need to turn to Apple Service Diagnostics at a technical level to find out as much information about the problem as possible.
Recover files from a damaged Mac drive
If your disk gets corrupted without repair, there is a chance that you will lose some of your data. The first step is to try to create a drive image, as you will need to connect a spare external drive that is no smaller than the startup disk you are trying to save.
Boot your Mac into recovery mode with
Cmd + R When the boot starts, then run Disk Utility. In the menu bar at the top of the screen, select
ملف -> صورة جديدة -> صورة من "Macintosh HD" (or whatever your drive is labeled).
Select the external drive and start the process. This can take some time, and if the drive is damaged it may fail completely. If this process is successful, a DMG file will be created for your old drive which you can mount and arrange as you need.
Copy files manually
If the option to create an image fails, you will need to manually copy your files. You can do this in recovery mode, but you will need to boot Terminal On startup instead of Disk Utility. To do so:
- Connect the external drive that you want to use as the destination for your files.
- Restart your Mac in recovery mode by pressing
Cmd + ROn startup, then choose Terminal.
- Use the command
cp -rTo copy your files to the external drive. for example:
cp -r /Volumes/Macintosh HD/Users/[username]/Documents /Volumes/Backup/
Let’s explain the above:
cp is the copy command, and
-r Makes this command run repeatedly. This means that all directories will be copied within the directory you specify, then directories within it, and so on.
first track It is the location of the files you want to copy. Note the backslash
() in the pathname, which you use to specify directories that have a space in their name. second track is the location of your external drive, which will always be in
/Volumes/ With whatever label you gave it to (in the example above, the drive is labeled “Backup”).
The problem with this approach is that you will need to remember where your files are. You’ll also need to hope they aren’t stored on a portion of the damaged drive. With your files safe, you can go to the option to repair your Mac and reinstall macOS.
The importance of backing up your computer
We hope you can recover the drive or any important files you may need. Even with a successful recovery and the many tools at your disposal, there is nothing quite like the peace of mind that a recent backup provides.
You don’t even have to use Time Machine to keep your Mac secure. Why not try one of our other Mac backup tools?
If your Mac is working fine, but you’re having other issues due to incorrect file permissions, learn how to fix disk permissions on macOS.