Helloafter rebooting the server, i keep getting these errors in mail.err : Apr? 7 06:08:09 main dovecot: master: Error: systemd listens on port 143, but it's not configured in Dovecot. Closing.????????????????????????????????????????????????? Apr? 7 06:08:09 main dovecot: master: Error: systemd listens on port 993, but it's not configured in Dovecot. Closing.????????????????????????????????????????????????? Apr? 7 06:08:09 main dovecot: master: Error: systemd listens on port 993, but it's not configured in Dovecot. Closing.????????????????????????????????????????????????? And then dovecot refuses any connection. the problem is solved if i do a manual restart of dovecot.service. After some search, i found 2 different solutions, one suggesting disabling dovecot.socket completely, the other one adjusting its settings: https://sowhatisthesolution.wordpress.com/2015/04/27/upgrading-dovecot-debian-wheezy-to-jessie/http://appbead.com/blog/fix-errors-reported-in-syslog-for-debian-8-jessie.html I also found an old thread in the mailing list that might be relevant: http://dovecot.org/list/dovecot/2012-March/134376.html The errors indeed seem to go away if i disable dovecot.socket . I would be grateful is someone could help me understand the role of dovecot.socket , and why that error happens and what is the right way to solve it? PS: I am using Ubuntu server 15.10 and dovecot package v2.2.18 Best Regards,