- Plesk for Linux
- Plesk for Windows
The system does not block mail from IP’s listed at DNSBL providers configured in Tools & Settings > Mail Server Settings > DNS zones for DNSBL service, for example,
Some public DNS providers implement non-hijacked responses for known DNSBL zones like Spamhaus.
Check what DNS resolvers you are using: If free DNS servers like Google Public DNS are used, in most cases you will receive a not listed (NXDOMAIN) reply from Spamhaus’ public DNSBL servers. Use your own DNS servers when doing DNSBL queries to Spamhaus.
Reference: spamhaus FAQ
In other words, commonly used public resolvers such as Google’s
18.104.22.168 / 22.214.171.124 and
126.96.36.199 – 188.8.131.52 would not work with Spamhaus.
Proper DNS response:
# dig +short TXT 184.108.40.206.zen.spamhaus.org
As a workaround, you can specify other DNS servers. For example,
OpenDNS Home :