unexpected error during installation

>>> in  apply configuration>>> preparing authentication plugin change failed to intall >>> it throws me an error which is mentioned below
Beginning configuration step: Preparing authentication plugin change

Creating a temporary user account for connecting with new authentication plugin during the step that updates security settings that runs later on (to avoid updating the root user account at this early stage where intermediate configuration steps might fail)...
An error occurred while trying to create the temporary user account.
Ended configuration step: Preparing authentication plugin change