In the Applications folder, select Utilities10. Go back to Finder and select Applicationsĩ. In the Erase tab, select the macOS Extended format and click EraseĨ. Open Disk Utility and select your external drive from the sidebarĦ. In the Applications folder, select Utilitiesĥ. Connect a USB flash drive or an external drive with at least 16GB of storageĤ. To revert to Mojave from Catalina, you need to have a bootable installer.Ģ.

Select Allow booting from external mediaĢ.

Select an admin account and enter the password.

From the menu bar, select Startup Security Utility.

In the macOS Utilities menu, select Utilities.

Select a user account and enter its password.

Press and hold Command (⌘) + R once you see the Apple logo.

Although undoubtedly useful, these default security settings should be changed to allow you to reinstall macOS Mojave from a bootable installer. Mac models with the Apple T2 Security Chip are protected against unauthorized access by their External Boot settings. Therefore, grab an external storage device and follow this guide to backing up your Mac. Prepare for reverting from Catalina to Mojaveīefore you go ahead and uninstall Catalina, complete the following actions: Back up your MacĬhances are, you’ve spent enough time with your favorite device to accumulate gigabytes of valuable information that will be missed dearly after you wipe your Mac’s startup disk.

You can always downgrade macOS Catalina to Mojave, and our step-by-step guide is here to help. Is it a major cause for concern? Not really. You know, the one where the new macOS performs far worse than expected. You’ve enthusiastically installed macOS Catalina only to run into the expectation-versus-reality scenario.

Install macos from time machine backup