On Drupal 7, you suddenly experience a login user page being redirected to a non-working or blank page at /user/login?destination=user. On below example, you notice the login form will not work as no form fields are being displayed. Even on source code, the same form fields are missing.
Joomla login error to offline website for Registered users: cannot access the private section of this site
March 06, 2016
If logging in to your offline Joomla website as Registered users and you encounter the log-in error: "cannot access the private section of this site", you may try the following fixes: