Open Relays were once the primary means of delivering email on the Internet. Any mail server would allow any other computer to send email through it. This spirit of co-operation that the Internet was founded on was soon exploited by individuals and companies who wished to send unsolicited email. This led to the introduction of security measures that only allow authorised systems to relay email.
Many of our customers have used the introduction of Broadband Internet access as an opportunity to run their own mail servers. While the majority of individuals who have taken this step are security conscious and most mail servers are by default closed to open relaying, the Virgin Media Acceptable Use Policy team does get reports regarding customers who have installed mail servers and are openly relaying email.
If any of our customers intend to install or run a mail server for use with their Virgin Media Internet connection we would ask that they read and follow these instructions:

Online security is essential, so we provide anti-virus & firewall protection free to our customers.