I'm having a very strange problem: Most user roles can login without a problem (administrators, clients, etc...).
But users with the 'registered user' role can not login through the form. The login form does not respond. In the log messages the failed login attempts are not logged.
The only way the users (with role 'registered user') can login is through the request new password link. So the user clicks on the link, receives an email with a login link, and when they click on the link in the email they are logged in. So than they can edit their account and even change the password.
However, when they log out again and try to login with the new password it does not work anymore, the form does not respond again.
The only way that user can get logged in again is through the request new password procedure.
Anyone have any idea what could be causing this?
Any help would be greatly appreciated.