urgent !!! deployment with "unauthorized user"

Hello,
i have a problem after deployment (default way) of my project:
i am using “group security” mode, with 2 users different: an administrator and a middle user. the administrator user can log whithout any problem on the system, but the second user, it can not log to the system and have the message “unauthorized user” . i think that there is a problem of permissions in the server system, the sever is under linux debian. some one can help me please???

Imho this is not a bug and you already posted this on two other spots.