Recipient blacklisted by the Reverse DNS test RSS


I'm receiving this error in the log file:

Recipient blacklisted by the Reverse DNS test (no DNS MX or A/CNAME record for domain "").

However, when I do an nslookup on the email server, the server appears to have an MX record. MX preference = 10, mail exchanger = internet address =

Any ideas?

by Aaron Wetherhold 8 years ago

Perhaps because the rDNS record for that ip doesn't match the domain.

Reverse DNS for
Location: United States [City: Chicago, Illinois]

The reverse DNS entry for an IP is found by reversing the IP, adding it to "", and looking up the PTR record.
So, the reverse DNS entry for is found by looking up the PTR record for
All DNS requests start by asking the root servers, and they let us know what to do next.
See How Reverse DNS Lookups Work for more information.

How I am searching:
Asking for PTR record: says to go to (zone:
Asking for PTR record: [] says to go to (zone:
Asking for PTR record: Reports [from]

Answer: PTR record: [TTL 14400s] [A=]

by mikeg 8 years ago

@Aaron Wetherhold: Is this a local domain? If yes, is the DNS server configured in ORF is the authoritative DNS for See

by Krisztian Fekete 8 years ago
(in reply to this post)


I thought the Reverse DNS test in ORF only looked for an MX or A record to exists (or only a MX record if that option is checked). I didn't think the PTR record was checked on this test. Am I wrong?

No, this is not a local domain. It is a domain owned by a customer of ours.

by Aaron W. 8 years ago

@Aaron W.: The PTR record is checked only if the Enable Sender IP Reverse Name Validation checkbox is checked under Configuration / Tests / Reverse DNS Test, and in that case, ORF would have logged that no PTR record was found. The domain seems to have both MX and A records, so I guess it must have been some DNS related issue. Did you use the same server for nslookup as the one configured in ORF?

by Krisztian Fekete 8 years ago
(in reply to this post)


I did nslookup on the same server, but this is now the second time I've had a weird DNS issue. I think one of my internal DNS server is having problems.

Thanks for the assistance.

by Aaron W. 8 years ago

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