What is an “Open Relay” or “Mail Relay”?
A. An open/mail-relay is a mail server which is not configured properly to prevent anyone on the Internet from using it to send e-mail messages. It is often the result of an organization not understanding how to configure security settings on mail servers. Spammers search the Internet for open/mail-relays and then “program” them to send a continuous stream of spam. After a short while the spammer has moved on to another open-relay.
