This might prevent the error from showing up again. In some cases, you may need to erase the drive first before reinstalling macOS. Reinstall macOS After Erasing the Drive First to Try Skirting ‘Error Occurred While Preparing The Installation of macOS’ Start your Mac again in Recovery Mode, then click Reinstall macOS.Select your disk (usually Macintosh HD).If your Mac has an Apple silicon chip, just hold the power button until you see the Startup Options menu. When you see an Apple logo or some other image, release the keys. Restart your Mac, and then press and hold the Command + R keys right away after you hear the chime.To repair your disk and reinstall macOS without erasing the drive, follow the steps below. Now, restart your Mac and try the installation again. Set the data and time automatically by going to System Settings > General > Data and Time > Set time zone automatically. Incorrect Data and Time Settings Might Cause ‘Error Occurred While Preparing The Installation of macOS’Ĭorrecting your Mac’s Date and Time settings might solve issues with the “error occurred while preparing the installation” popup.

Hopefully, after doing the steps above, the message “an error occurred while preparing the installation of macOS” will no longer appear when you try to reinstall macOS Sierra or later. Now, proceed with trying to reinstall macOS.

You may be asked to log in twice, depending on when the Safe Mode message appears.

Restart your Mac, then immediately press and hold the Shift key until the login window appears.

If you’re using an Intel-Based Mac, follow this procedure.

Wait for your Mac to restart, and you should see “Safe Mode” when the login window reappears.

Press and hold the Shift key, then click Continue to Safe Mode.

When completely shut down, press and hold the power button until “Loading Startup Options” appears.

To boot your Apple Silicon Mac into Safe Mode, follow these steps. The process of rebooting in safe mode differs between Apple Silicon Macs and Intel-based computers. The first thing that you should try is to boot your Mac into Safe Mode. Let’s walk through some possible ways to resolve this error. This has happened often happens when reinstalling macOS Sierra, but it’s also been known to happen with newer versions.

One example is a pop-up that reads, “an error occurred while preparing the installation of macOS Sierra.” Following that, you’re prompted to “try running this application again. On a somewhat frequent bases, installing or upgrading macOS halts with a message suddenly appearing.

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