R2B2 networks

E-Mail Problems?

Here at R2B2 Networks we use a number well known blacklists and other techniques to reduce spam volume, but inevitably false positives will creep in.


If an R2B2 Networks server is bouncing your messages then please check your configuration.

Many spam messages are generated by 'zombie' machines that are being abused without their owner's knowledge. Most of these machines will not be correctly configured to act as a sending mail gateway and therefore we are very strict with mis-configured mail servers.

Some simple checks you can do:

  • Check the reverse DNS entry on the IP of sending server - make sure it matches the forward entry.
  • Ensure that sending servers say 'HELO' with the correct name, and this matches forward/reverse DNS.
  • Make sure the 'HELO' name is fully qualified (a FQDN).
  • When using forum, online shopping cart of other software which sends out messages, make sure the 'From' and 'Return-Path' headers are real addresses that will accept mail.


Blacklists are out of our control - if you have mail rejected as a result then see the relevant link for that blacklist that should have been returned and ask them about removal.


If you are still having problems with E-mail, or do not receive a reply, please use the direct contact form.

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