Hello. Debian 4.9.168-1+deb9u4 (2019-07-19) x86_64 ISPConfig Version: 3.1.14p2 single Nginx I received a lot of spam every day so I have a drastic system in place: the new user has to sign up from a form and its email address is added to a whitelist. If the FROM (De in French) of the received message is not in the whitelist or does not contain the "secret text" in SUBJECT (Objet in French), then it is rejected with a message and a link referring to the registration by the form. Can we easily create this type of negative rules in ISPConfig? – If yes: how to proceed? – If no: is there a How to install ManageSieve on ISPConfig on Debian Nginx? To install Roundcube, I followed the tutorial "The Perfect Server - Debian 9 (Nginx, BIND, Dovecot, ISPConfig 3.1) - Page 3 paragraph 18". I set Server config: with [SERVERNAME]:8081/webmail/ I got the error message "config.inc.php was not found", so I then followed the tutorial RoundCube error: config.inc.php was not found.