Your Mac restarted because of a problem: what to do

Why it happens

This message means your Mac hit a serious error, called a kernel panic, and restarted itself to protect your files. The usual cause is an out-of-date app or driver, or an accessory such as a USB hub, dock or external drive. Less often it's a hardware fault inside the Mac. One panic after an update is rarely a worry, but repeated ones need tracking down.

How to fix it

1. After the restart, click Report if the message offers it. The report goes to Apple and the details window sometimes names the app or driver involved, so note any name you recognise.

2. Install any waiting macOS update in General, then Software Update. Panics caused by bugs are often fixed in the next update.

   General›Software Update

3. Update your apps too. For App Store apps, open the App Store, click Updates and choose Update All. Apps from elsewhere usually have Check for Updates in their own app menu.

   App Store›Updates›Update All

4. Unplug everything except power: USB hubs, docks, external drives, card readers, monitors and audio gear. Use the Mac on its own for a day. If the restarts stop, plug things back in one at a time, a day or so apart, to find the one causing it.

5. Test in Safe Mode, which starts the Mac without extra drivers and login items. On a Mac with Apple silicon, shut down, then press and hold the power button until the startup options appear. Select your disk, hold Shift and click Continue in Safe Mode. On an Intel Mac, restart and hold Shift until the login window appears.

6. Use the Mac in Safe Mode for a while. If it never panics there, the cause is software or an accessory, not the Mac itself. Restart normally to leave Safe Mode.

Still not fixed?

1. Check what starts with your Mac. In Login Items & Extensions, turn off items you don't need, and remove apps that add drivers, such as old antivirus, VPN, audio or USB tools, especially anything installed just before the panics began.

   General›Login Items & Extensions

2. Back up with Time Machine, then reinstall macOS from Recovery. This replaces the system files and keeps your own files and apps.

3. Run Apple Diagnostics to test the hardware. Unplug accessories and shut down. On Apple silicon, hold the power button until the startup options appear, then hold Command-D. On an Intel Mac, hold D right after you press the power button.

4. Contact Apple Support or book a repair if the Mac still panics in Safe Mode with nothing plugged in, or if Diagnostics reports a fault. At that point it's most likely hardware, such as memory or the logic board, and needs a technician.