HTTP 403 Forbidden
The 403 Forbidden status code (sometimes called “access denied”) is displayed when a user is not authorised to view a certain page. Thus, the server understands the client’s request but cannot comply without authorisation.
Web admins define the various types of access restrictions in the .htaccess file, which means they can make the page inaccessible to everyone or only to particular IP addresses. In addition, the appearance of the 403 error message page can be customised; the same goes for the error message 404 – page not found.