Authentication failed. Roundcube and rainloop

After DataCenter force reboot server. Users can't login roundcube and rainloop with useame and password.

[11-Apr-2018 21:52:48 +0100]: IMAP Error: Login failed for [email protected] from 213.123.45.85. AUTHENTICATE PLAIN: Authentication failed. in /var/www/html/roundcubemail-1.3.4/program/lib/Roundcube/rcube_imap.php on line 196 (POST /roundcube/?_task=login&_action=login)

ı found this but cant fixed: http://forum.directadmin.com/showthread.php?t=54050

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