Spam policy

General

Do not send attachments or HTML mail to addresses like hostmaster, postmaster or webmaster. These will be rejected! Use plain text instead!

Junk mail sent to this system will always be met with a formal complaint, often resulting in termination of the offending account.
Bessides that, spam is forwarded to SpamCop and Pyzor.

Hosts without a working abuse or postmaster account or broken whois or ipwhois are reported to RFC ignorant org.
In case of mass mailings from or on behalf of a company registered in the Netherlands, a complaint is filed with the Onafhankelijke Post en Telecommunicatie Autoriteit (dutch) and XS4ALL (dutch), which may lead to civil liability (dutch) and criminal prosecution. Persistent NL spammers are also reported at the Registratiekamer / College Bescherming Persoonsgegevens (dutch).

The OPTA can impose fines up to € 450,000.-.
The CBP can impose fines up to 10 % of the annual gross turnover.
XS4ALL charges € 50.- per instance of any spam sent to any customer and has the legal muscle to back this up!

Spamming is a criminal offence in the entire European Union. It is illegal to send spam to: at be cy cz de dk ee es fi fr gr hu ie it lt lu lv mt nl pl pt se si sk and uk.
All EU spam will be handed over to the relevant NRA. All non EU spam will be forwarded to the appropriate embassy. Persistent non EU spammers may face extradition.

Mass mailings which are the result of notoriously vulnerable email clients or - servers being infected by a worm are considered to be UBE. The same applies to so called 'email virus warnings' (which are in effect anti virus software spam) and fake (joe job) bounces.
DSN's ('MAIL FROM: <>') should always contain the full headers of the original message. Bounce messages which do not contain all header lines or bounces of messages which did not originate from this system (joe job) are rejected by this system.

Mail from hosts of which the reverse lookup doesn't succeed or match, mail from hosts which are in a domain without a MX and mail of which the sender or recipient can not be verified, are rejected by this system. The same applies to email without a HELO / EHLO that matches the IP nr or an IP nr that matches the HELO / EHLO, sensible subject or RFC compliant Message-Id.
Mail from hosts blacklisted by the organisations mentioned above is also rejected. These blacklists include persistent spammers, domains without a valid abuse or postmaster account and domains with a broken whois registration.
Mail which contains spam-specific strings is also rejected by this system.

Mail from yahoo.com is only accepted from hosts in the same domain.

All rejected mail is logged!

How this system filters mail

• Syntax check
  The entire SMTP session should use a correct syntax.
• Reverse lookup
  This host will do a reverse lookup of the remote host's IP address. If this fails the mail will be refused. If the reverse lookup succeeds it will lookup the remote host's IP address. If this fails mail will be refused.
  This of course also means that if your system administrator or ISP is too lazy or stupid to configure their nameserver correctly, your mail will be refused.
• Remote host MX check
  The remote host has to be in a domain with a MX. The MX has to be a hostname and should not resolve to '127.0.0.1' or RFC 1918 addresses.
• Helo check
  The HELO / EHLO should be a Fully Qualified Domain Name. The name should match the IP address or vice versa.
  This of course also means that if your system administrator or ISP is too lazy or stupid to configure their mailserver correctly, your mail will be refused.
  To limit false positives this system will also try to match the domain part, without the tld, of the helo and the hostname.
  If this also fails it will lookup the MX of the helo and try to match that with the hostname.
• Blacklists
  Besides a local blacklist, the following distributed DNS based blacklists are used:
  • virbl.bit.nl
  • Distributed Sender Boycott List
  • Open Relay Data Base
  • RFC ignorant org
  • SpamCop
  • The Spamhaus Project
  These lists blacklist either the IP address or sender domain.
• Spam check.
  If the mail is tagged as spam (Subject: *****SPAM*****) by the upstream host, it will be rejected.
• Sender and receiver verification.
  It does this for both the content and transport to and from. It does this by means of a 'Callout':
  The mailserver makes SMTP connections to the remote MX(es), to test whether a bounce message could be delivered to a sender address, or whether the current message could be delivered to a recipient address. For a sender address, it sends:
  

    HELO <primary host name>
    MAIL FROM:<>
    RCPT TO:<the address to be tested>
    QUIT
    

  If the 'RCPT TO:' causes an error, a fake email address is used and the mail will be rejected.
  The existence of postmaster is tested in the same way.
  
• SPF
  Sender Permitted From. A way to prevent joe-jobs.
• Size checking
  Large email's are rejected by this system. The size check is done both after RCPT and just before completion of the DATA phase.
  
• Message-Id
  The message should have a RFC compliant Message-Id. The correct format is; Some_Unique_String@Host.Domain.Tld eg;
  Message-Id: <E1BnfcM-0000bf-GI@mail.example.com>
• Mime checking
  Certain mime types are not accepted by this system.
• Virus check
• SpamAssassin
  SpamAssassin is a program which looks for spam specific strings.
• SURBL
  The Spam URI Realtime Blocklists lists sites advertized in spam.
• DCC
  Distributed Checksum Clearinghouse is a blacklist which blacklists hashes of known spam message bodies.
• Pyzor
  Pyzor is a blacklist which blacklists hashes of known spam message bodies.
• Razor
  Vipul's Razor is a blacklist which blacklists hashes of known spam message bodies.

Information on fighting junk mail and spam

If our spam policy prohibits you from sending me email, use our web based form instead.