If your Mac starts up to a circle with a line through it
A circle with a line through it means that your startup disk contains a Mac operating system, but it's not a macOS that your Mac can use.
![Circle with line through it screen](https://cdsassets.apple.com/live/7WUAS350/images/macos/macos-startup-circle-with-slash-circle-with-line.png)
A prohibitory symbol, which looks like a circle with a line or slash through it, means that your startup disk contains a Mac operating system, but it's not a version or build of macOS that your Mac can use.
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 laptop computers that have Touch ID, press and hold Touch ID.)
If Disk Utility found no errors or repaired all errors, reinstall macOS.
If you still need help, please contact Apple Support.