Real time Blacklists (RBL/DNSBL)

A DNSBL (commonly known as a 'Blocklist") is a database that is queried in realtime by Internet mail servers for the purpose of obtaining an opinion on the origin of incoming email. The role of a DNSBL system is to provide an opinion, to anyone who asks, on whether a particular IP Address meets the policy for acceptance of inbound email.

We can also skip checks on blacklisted addresses if a user has authenticated with us, so even if you're blacklisted unfairly, we can still relay your mail

We make use of the following RBL providers:

• spamhaus.org -- mainly lists the very large spam companies.
• spamcop.net -- list spam companies.
• dnsbl.njabl.org -- lists those companies whose mail servers are configured in a way that they can be hijacked by spam providers and companies.
• rfc-ignorant.org -- list those organizations who did not correctly register their mail server domain name (a tactic most commonly used by spam companies and providers).
• relays.visi.com -- lists those companies whose mail servers are configured in a way that they can be hijacked by spam providers and companies.