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akhilexx Author

Level 1

8 points

Reverting back to MacOS Catalina

Recently I had upgraded to Big Sur,but dur to lagging issues and application support I decided to revert back to Catalina using Time Machine backup.But when I reinstalled the OS it just doesn’t load in the startup and says unrecoverable error:prelogin .

I also tried reinstalling the Catalina OS from recovery mode ,but it says resources not available to install this version of MacOS .

What should i do now?

MacBook Pro 15″, macOS 11.0

Posted on Dec 7, 2020 8:57 PM