Roundcube 0.82 connection failed

[linux_99]

Hi,

     I installed Roundcube 0.8.2, backend mysql , OS ubuntu 12.04, dovecot and postfixadmin

Log (mail.err)
Oct  8 13:25:31 smtp roundcube: IMAP Error: Login failed for [email protected] from 192.168.126.22. LOGIN: Authentication failed. in /usr/share/apache2/roundcubemail-0.8.2/program/include/rcube_imap.php on line 191 (POST /mail/?_task=login&_action=login)


Does anyone have any idea for this connection issue ?