GreenNet provides a unique anti-spam service geared to NGOs, the voluntary sector, charities and activists.

All our membership services provide good anti-spam measures, based on open-source software that we are continually developing, and also on anti-spam rules and databases.  These measures are designed to allow genuine phrases in email relating to health, peace and social justice campaigning to reach you intact, while keeping out phishing, conference scams, trojans, viruses and generic spam.  

This "filtering" is a three-stage process:

  • perimeter checks including greylisting which stop 80% of attempts to send spam before the message content is even seen;
  • checks to reject certain obviously spammy content and a small number of known sender addresses;
  • a sophisticated scoring mechanism using a customised version of SpamAssassin which rejects a further proportion of spam, and also marks suspect but not definite spam in the headers so that this can be treated differently by the user or another relay (see filtering out spam for further details).


If you need to run your own office mail server, you can collect filtered email via POP (for example, using an Exchange plugin like POPWeasel) or IMAP or we can forward to your local server using SMTP.  In the last case, where you collect your email via SMTP, you will ideally want to restrict the range of servers you will accept mail from in your firewall or office server.  Our mailbox accounts, which are associated with the anti-spam service, can also be used as a smarthost for outgoing mail, and we may ask that organisations running an Exchange server prevent backscatter by using our anti-spam, or reconfiguring their servers.

We do even better where we have control of the "perimeter" of the domain. This means the MX record of your domain should be pointed to our servers, and ideally the domain should be registered with us. Our services include the cost of renewal of a domain ending, .org, .info and so on and either a certain amount of webspace or web forwarding.

We can provide an optional weekly or daily report summarising and listing all sender addresses that have been prevented from delivering email because of one or more countermeasures against spam.  The occasional wrongly-labelled email can be reported to us either to automatically update the shared filters, or to our support team. This is very useful feedback for us (as is reporting any spam that is received).  We also may report trapped spam intended for you on your behalf or use it for anti-spam development.

Different levels of membership have different limits for the number of emails sent and received.  Home/Activist Plus membership (at £90+VAT per year) includes anti-spam and anti-virus measures for one domain, up to an average of 2,000 accepted and scanned emails per day (this will therefore exclude some spam that is excluded via perimeter defences), effectively an all-in email service for a domain for a small organisation.