Mail servers accept messages for recipients that have their mailboxes hosted on the mail server itself. Any attempt to send a message to a non-local recipient (i.e. a recipient on a different mail server) is called a ‘relay’. It is critical to regulate who can send messages to others (non-local recipients) or the server will be identified as an Open Relay. This means that people on the Internet can send email out through the server without authenticating. Secure the server by configuring strict rules as to who can relay messages to non-local recipients.
For a server on the Internet, the best relay setting to have is to only have Allow relay for authenticated senders checked, and leave Allow relay for local sender addresses unchecked. This will make everyone who wants to send email out via the server provide a username and password.
To access the SMTP Relay options, open the Administration program, expand the Servers >Localhost >Connectors branch, right click on the SMTP icon, select Properties from the popup menu, and click the Relay tab.
The following provides an explanation of the various relay settings. Source www.mailenable.com
For a server on the Internet, the best relay setting to have is to only have Allow relay for authenticated senders checked, and leave Allow relay for local sender addresses unchecked. This will make everyone who wants to send email out via the server provide a username and password.
To access the SMTP Relay options, open the Administration program, expand the Servers >Localhost >Connectors branch, right click on the SMTP icon, select Properties from the popup menu, and click the Relay tab.
The following provides an explanation of the various relay settings. Source www.mailenable.com
