Registering a user via REST is an important process particularly when the requests come from a mobile device. In working through the process you might have come across error message like: 403 Forbidden : "Only anonymous users can register a user." 422 Unprocessable Entity : "A Password cannot be specified. It will be generated on login."So how did I get these and what to do? First off, check the REST set up in the administration area of Drupal.  Configure User and User registration...