Can't login to Roundcube (users table empty?!)

[amine]

I stopped ufw but it still doesn't work.
When I try to login to roundcube I got these two errors:

in /var/sentora/logs/sentora-access.log:

Code:

105.235.137.6 - - [18/Nov/2016:11:23:55 +0100] "POST /etc/apps/webmail/?_task=login HTTP/1.1" 200 2730 "http://panel.domain.com/etc/apps/webmail/?_task=login" "Mozilla/5.0  Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/54.0.2840.87 Safari/537.36 OPR/41.0.2353.56"

in /var/sentora/logs/roundcune/errors/log:

Code:

[18-Nov-2016 11:23:55 +0100]: IMAP Error: Login failed for contact@mywebsite.com from 105.235.137.6. Could not connect to localhost:143: Connection refused in /etc/sentora/panel/etc/apps/webmail/program/lib/Roundcube/rcube_imap.php on line 184 (POST /etc/apps/webmail/?_task=login?_task=login&_action=login)

N.B: here I changed my server and website adresses to "panel.domain.com" & "mywebsite.com" just to avoid web scrappers.

I found some posts suspecting dovecot, so I checked its log but it was empty.

While checking Sentora installation log, everything was fine except these lines:

Code:

-- Installing Postfix
ln: failed to create symbolic link ‘/etc/postfix/master.cf’: No such file or directory
ln: failed to create symbolic link ‘/etc/postfix/main.cf’: No such file or directory

...
Daemon run complete! (23:41 14th Nov 2016 CET)

-- Installing Logrotate
ln: failed to create symbolic link ‘/etc/logrotate.d/Sentora-apache’: File exists
ln: failed to create symbolic link ‘/etc/logrotate.d/Sentora-postifx’: File exists
ln: failed to create symbolic link ‘/etc/logrotate.d/Sentora-dovecot’: File exists
chattr: Operation not supported while reading flags on /etc/resolv.conf
Failed to restart postfix.service: Unit postfix.service failed to load: No such file or directory.
Restart your server now to complete the install (y/n)?