Here are 10 ways to resolve macos 10.15 keychain problems. As a result, “How can I repair a keychain in Catalina” is a question bugging many users of the newly-released OS. Keychain operations need to roll out smoothly at all times, but every once in a while, they can be disrupted. Keychains are a system of credentials such as passwords, encryption keys, security certificates, etc., for managing your access to various password-protected programs.