Time Machine is a backup utility built-in to macOS, allowing you to back up your entire Mac. If you have complaints like “I updated my Mac and lost everything” or “Mac update deleted everything”, the best possible solution is to get things back from Time Machine backup. Restore lost files after Mac update from Time Machine backup Before upgrading to macOS Big Sur or Catalina, please be aware of possible data loss and try to minimize the possibility.
Note: Before you get all your lost data back, it’s recommended not to put new data to your Mac in case that the lost files would be overwritten by new data.
