I have changed Dovecot's mysql connection string. The former was: host=localhost dbname=mailserver user=mailuser pass={your mailuser password} This produces the following error at ''/var/log/maillog'': Apr 1 17:54:23 darkstar dovecot: auth: Fatal: mysql: Unknown connect string: pass The comments in ''/etc/dovecot/dovecot-sql.conf.ext'' clearly states: # Database connection string. This is driver-specific setting. ... # mysql: # Basic options emulate PostgreSQL option names: # host, port, user, password, dbname This is also confirmed by Dovecot's [[http://wiki2.dovecot.org/AuthDatabase/SQL#Examples|documentation]]: # The mysqld.sock socket may be in different locations in different systems. # Use "host= ... pass=foo#bar" with double-quotes if your password has '#' character. connect = host=/var/run/mysqld/mysqld.sock dbname=mails user=admin password=pass # Alternatively you can connect to localhost as well: #connect = host=localhost dbname=mails user=admin password=pass I have also followed the advice on double quotes for special characters in the password. So, the new connection string is: "host=localhost dbname=mailserver user=mailuser password={your mailuser password}" This change refers to Dovecot v2.2.13. By the way, I would like to thanks [[wiki:user:astrogeek]] for this article. It's quite precise and clear! --- //[[wiki:user:denydias|Deny Dias]] 2015/04/01 18:36//