If you're using built-in authentication, you can block unauthenticated people from being able to create an account.

  1. Rocketship icon for accessing site admin settingsIn the upper-right corner of any page, click .

  2. Management Console tab in the left sidebarIn the left sidebar, click Management Console.

  3. Privacy tab in the settings sidebarIn the left sidebar, click Privacy.

  4. Enable sign-up checkboxUnselect Enable sign-up.

  5. Save settings buttonUnder the left sidebar, click Save settings.