If an error occurred while updating or installing macOS

The message might say that an error occurred while downloading, preparing, or installing, or that the software is damaged, could not be verified, or failed to personalize. The cause of messages like these can vary, and sometimes they're only temporary. Try these solutions.

Check storage space

If the message says that your Mac doesn't have enough storage space, free up storage space.

Check your internet connection

The installer needs a stable internet connection to get firmware and other information specific to your Mac. Make sure that your Mac is connected to the internet.

Install from macOS Recovery

If you’re installing from the App Store, Software Update, or the Finder, it might help to start up in safe mode before installing.

Otherwise, install macOS from macOS Recovery to ensure that no other software on your Mac can interfere with installation.

Repair your startup disk

Use Disk Utility to repair your startup disk.

If you’re using a previously downloaded installer that your Mac says is damaged or can’t be verified, delete it and download the installer from Apple after repairing your disk.