What is a Kernel Panic on Mac and How to Fix it?

How to solve Kernel Panic error

What is Kernel Panic?

Kernel Panic, though sounding scary, is simply an occurrence when your Mac keeps restarting for no obvious reason. Your Mac’s screen goes black giving you various warning messages like “You need to restart your computer.” Note that the presence of the warning message is what distinguishes Kernel Panic from usual Mac restarts and app crashes. In other words, Kernel Panic is just a Mac version of “blue screen of death” on Windows, but luckily, it can be fixed. So, let’s face the issue head-on.

You need to restart your computer - Kernel panic Error Message

What happens is your Mac encounters a critical error that it can’t handle, so it automatically shuts down. If it happens rarely enough (like once in a few weeks) that shouldn’t be a trouble. A basic restart should help it. It’s worse when Kernel Panic happens regularly, especially if your Mac crashes right on startup. It might be a sign of a damaged hardware, which isn’t funny, given your Mac is almost unusable by that time.

What’s causing Kernel Panic on Mac

There are a million reasons. One user reported he had simply installed the iTunes folder on a different drive than a system one. But in 90% of cases software conflicts are to blame. Here’s a list of main suspects:

  • Not enough RAM and lack of hard drive space.
  • Outdated drivers or plugins
  • Broken disk permissions
  • Conflicting apps
  • Hardware issues and incompatible peripherals

The first step should be to isolate hardware issues from software-related ones. It may be a combination of both, like when your RAM has turned off, while two apps are conflicting for memory. Anyway, there’s a path, laid out by great Mac experts which will now follow immediately.

Software solutions to fix Kernel Panic on Mac

1. Update all your software

Start by launching App Store app through Spotlight or Apple menu. Go to App store and click Updates to see the latest updates available for your Mac. If some tools haven’t been updated for long, it may well be the root of the Kernel Panic problem.

 2. Find which apps are corrupted

If your Mac keeps crashing on a particular app, you know which one is to blame. That’s what you should do in this case:

  1. Try updating the problem app and then reboot your machine.
  2. If there's no updates or you cannot run them, delete and reinstall the entire app.
  3. Alternatively, use a dedicated app-uninstaller tool.

If Kernel Panic occurs on random apps, you should look into deep-seated system drivers, specifically the ones that came with peripherals, like video cards, adapters, etc. Make sure you updated everything that deals with graphics, file system or networking. And, if it doesn’t help, here are more tricks.

3. Repair disk permissions

Sometimes applications are fighting each other in order to get access to files and folders. This is what disk permissions are all about. When your applications go awry, fixing broken permissions helps a big deal. Unfortunately, the option to manually repair disk permissions has been disabled in Disk Utility since OS X El Capitan. But if you are running OS X Yosemite or older OS, you need to:

  1. Restart your Mac holding Command + R
  2. Launch Disk Utility
  3. Click First Aid > Repair Disk Permissions
Use Disk utility Kernel Panic Mac

If you’re on macOS Sierra or OS X El Capitan, the easiest is to fire up an app, like CleanMyMac X. The app has an advanced Maintenance module where you can repair disk permissions in one click. It also has the Verify Startup Disk command that may help you find Kernel Panic source.

4. Ensure you have enough free space on drive

Apple recommends reserving at least 20% of free space on your startup drive. Your Mac needs enough room to breathe freely. But when there’s lack of physical or virtual memory, your Mac’s performance drags down and Kernel Panic is quite common.

  1. Choose Apple menu > About This Mac.
  2. Switch to the Storage tab.
Free up space on mac

If your main volume is approaching full capacity, then you ought to make more room on it. The obvious solution would be to delete unused apps or whatever old junk is stored there. Or simply leave it to a dedicated app to free up your drive. For instance, try this one as it’s reported to find 74 GB of junk on an average Mac.

5. Launch Disk Utility

Kernel Panic may happen due to corrupted files or issues with external devices. Fortunately, Apple partially took care of this with their built-in Disk Utility. Launching Disk Utility’s First Aid tool would detect any disk errors and if it can solve it, you’re lucky again.

  1. Choose Apple menu > Restart.
  2. Hold down Command + R while you restart the computer. 
  3. Go to Disk Utility > First Aid.

Follow the onscreen commands and expect to see something like “Operation successful” in the report. In the worst case scenario, you might get “The underlying task reported failure” which suggests a disk repair failed. At this point you should start thinking about saving your data and reformatting the drive.

6. Disable startup items

There is a good chance login items are the reason your Mac randomly restarts. With dozens apps launching on startup, they could be too many for your processor to handle. To troubleshoot Kernel Panic, now your tactics would be to disable these programs and check how your Mac is behaving.

To disable login items, follow this path:

  1.  Go to System Preferences > Users & Groups.
  2.  Select your username in the menu.
  3.  Switch to the Login Items tab.
  4.  Choose a startup item you want to disable and then click the “–” symbol.
  5.  Restart your Mac to enable the changes.

Now, it’s time to put on your detective’s hat as we’ll be investigating which login item has been causing Kernel Panic. This time we’ll go in the opposite direction and will be turning on the login items — one at a time. If your Mac crashes after the particular login app is enabled, congrats, you’ve hit right on the nail. Note that you’ll have to reboot after each step, but finding the root of the problem is intriguing, right?

BTW, if you’re uncomfortable messing with system settings, there’s an easy alternative. CleanMyMac X, the app we’ve mentioned above, has a lot of tools for deep-level Mac maintenance. And there is a feature to disable/enable Login Items as easy as pie.

  1. Download CleanMyMac for free.
  2. Launch it.
  3. Click on the Optimization module.
  4. Go to Login Items.

Disable startup apps one by one.

Hardware fixes to Kernel Panic

All the connected hardware could be responsible for the crash fever on your Mac — it happens quite often, actually. So, let’s walk through the hardware solutions to Kernel Panics. And be prepared to restart your Mac a few more times when you follow the next tips.

1. Turn off peripheral devices

Just as we did with startup items, we have to figure out which exactly device is conflicting with your system. Now, you need to plug off everything connected to your Mac: printers, external video cards, network adapters, etc. Restart your Mac and connect one device at a time — if nothing happens, restart again with the new device plugged in. This trial-and-repeat approach should isolate the reason for Kernel Panic. Found which peripheral is corrupted? Well done, now reinstall it and update the software that came with it.

2. Run Apple Diagnostics

Depending on your OS, this built-in tool may be called Apple Diagnostics or Apple Hardware Test. These advanced Apple’s utilities shouldn’t be reserved for geeks only — in fact, they really save lives (okay, Macs).

  1. Disconnect all peripherals.
  2. Choose Apple menu > Restart.
  3. Hold down D while you restart the computer.

Apple Hardware Test shortcut

Do nothing. Apple Diagnostics would launch automatically and test your hardware condition. If any problems are detected, you’ll get a detailed report which is now your official invitation to pay a visit to Apple Support.

The last-ditch solution to Kernel Panic

So, here we are. Nothing of the above helped and now you are desperately scrolling this on your friend’s computer (as your Mac keeps on crashing, obviously). In no way you should panic. Now, you can try a way that most definitely will save your Mac — reinstall your OS from scratch. It’s like starting a new life — and there’s nothing difficult to it.

If you’re running macOS Sierra, check out this article on how to reinstall OS.
Here you'll find instructions on how to reinstall macOS High Sierra.
If you wish to reinstall macOS Mojave, click here

To reinstall macOS Catalina, follow these steps.

Hope this tricks helped you eliminate Kernel Panic. Mac should maintain its reputation as the best computer in the world, so let’s keep it healthy. Share this article if you liked it and thanks for reading.

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