Kerio Connect - Administrators Guide - Kerio Software Archive

Protecting SMTP the server in Kerio ConnectWhy to configure the SMTP serverWhen correctly configured, the SMTP will protect your Kerio Connect from misuse. It enablesyou to define who will be allowed to send outgoing message via this server and what actionsthey can perform.Once an unprotected SMTP server is accessible from the Internet (anytime when at least oneMX record is directed to it and the port 25 is available for access), anyone can connect to theserver and send email messages through it (usually spam).Spammers may use your SMTP server to send out spam messages.company may be added to a spam blacklist.Thus yourHow to configure who can connect to SMTP serverTo configure SMTP settings, login to the administration interface:1. Go to section Configuration → SMTP Server → tab Relay Control.2. Select Allow relay only for.If you enable this option, users not specified will be able to send messagesonly to the local domains.3. Check Users from IP address group to specify a group of IP address which can sendoutgoing messages.Usually local addresses are added. However if you wish to protect userswho send messages from local addresses, check option Require authenticationwhen accepting message with sender from a local domain.4. Check Users authenticated through SMTP for outgoing mail to allow all Kerio Connectusers sending outgoing messages.92