Article ID: 121010, created on Apr 10, 2014, last review on May 11, 2014

  • Applies to:
  • Plesk 11.5 for Linux


We have configured spam protection with black listing. The system does not block messages are coming from blacklisted IP address. Server would not be rejecting mail from IP’s listed at


Some public DNS providers wisely implement non-hijacked responses for known DNSBL zones like Spamhaus.


Check what DNS resolvers you are using: If you are using a free DNS servers like Google Public DNS, in most cases you will receive a not listed (NXDOMAIN) reply from Spamhaus’ public DNSBL servers. Please use your own DNS servers when doing DNSBL queries to Spamhaus.


In other words, commonly used public resolvers such as Google’s ( / and – would not work with SpamHaus.

Proper DNS response:

# dig +short TXT

As workaround you can specify other DNS servers. For example, OpenDNS Home:

Search Words

server would not be rejecting mail from IP’s listed at


rbl blocking

a914db3fdc7a53ddcfd1b2db8f5a1b9c 56797cefb1efc9130f7c48a7d1db0f0c 01bc4c8cf5b7f01f815a7ada004154a2 29d1e90fd304f01e6420fbe60f66f838 0a53c5a9ca65a74d37ef5c5eaeb55d7f

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