Pre-requisites:

• You must be able to manage MX records for the domain to be filtered.
• Filtering system should be given a DNS hostname.
  It is not necessary for it to have a hostname entry for each domain that it is expected to filter for, but it must have a hostname in some domain. An MX record must contain a hostname and not an IP address.

To add a new domain to be filtered by your virtual mail scanner appliance, follow these steps:

• Log into your administration page
• Click on Tools/Links
• Click on Manage Domains and Mail Routing
• In "Sending Host" put the domain you would like to add to the filtering
• For the "Action" drop-down, select "Relay"
• In the "Mailer" field, type "smtp"
• In the "Relay Destination", enter the hostname of the delivery server
• Check the box marked "Also relay subdomains" if you will also be receiving email for a subdomain of the domain (most will not)
• Check the box marked "Skip MX"
• Click "Update"

Once you have completed these steps, change the DNS MX record for your domain to point to the hostname for the filtering system. Recommended:

• Avoid using "mail." as a hostname for your receiving server. Some spam networks will bypass an MX record and attempt to send directly to any server named "mail." If your webserver and mailserver are one in the same, ie: they share a public IP address, consider sending to "www."
• If possible, use firewall rules on the receiving server to accept port 25 connections only from the filtering system.