More serious problems

When a restart isn’t the answer

When should I reset the NVRAM or SMC?

> NVRAM is where your Mac stores settings such as your startup disk, connected devices and so on; the System Management Controller (SMC) handles the battery, heat, the power button and the light sensor. Resetting the former can solve startup issues; resetting the latter may tame unruly processes such as kernel_task. To reset NVRAM, power on while pressing å+ç+p+r. Hold the keys until the second startup chime or screen. SMC steps vary from Mac to Mac: check out bit.ly/apple-resetsmc for Apple’s guide.

How do I get my lost files back?

> Open the folder that used to contain the file(s) and then launch Time Machine. You can now use the arrow keys to move back in time. Select a file or folder and click Restore to bring it back. For a full restore, start in Recovery mode, reinstall macOS and restore from your Time Machine backup.

Why do I get a flashing question mark at startup?

> The ? folder means your Mac can’t use your startup disk. If it’s only there for a moment, reset the NVRAM (explained in the next step). If it’s persistent, power off your Mac and go into macOS Recovery. Use Disk Utility to scan and fix any disk errors. Still nothing? You’ll need to reinstall macOS.