We need more information. Is your mail server working connecting with an email client? What error do you get when you try to login using a round cube?

We can try to help but it connects with an array in the PHP file based on your setup.

Hi, I can not connect to RoundCube in the log I have this message:

Could not connect to ssl://mail.server.com:143: Connexion refused in /usr/share/roundcubemail/program/lib/Roundcube/rcube_imap.php on line 197 (POST /webmail/?_task=login?_task=login&_action=login)

I believe you’re trying to connect roundcube through imaps instead of imap. The port should be 143. Make sure you have tls enabled and check the Dovecot config the ensure you have imap only enabled to run netstat -ntlp |grep imap to see if 143 is opened and make sure it is open in the firewall.

Thank you for your reply but I have this error now :

SMTP Error : Connection failed : Failed to connect socket: connection refused …

See my post https://www.tecmint.com/install-and-configure-roundcube-webmail-for-postfix-mail-server/comment-page-1/#comment-916126

In config.inc.php;

instead of using ssl, use tls, eg;

$config[‘default_host’] = ‘ssl://[whatever]  <-- wrong
$config[‘default_host’] = ‘tlsl://[whatever]  <-- correct!!