Some customers have reported seeing all incoming mail being rejected. These customers have all used a DNSBL list called ORDB in the past.
What can be done to stop this happening?
The ORDB DNSBL has not been active for a considerable length of time. However it has continued to respond in such a manner as to allow all mail to pass checks unhindered.
As of 25 March 2008 the ORDB DNSBL servers have started responding to all queries indicating the message is spam, in an effort to stop people using their servers. This has resulted in a lot of genuine msil being rejected as spam.
We would urge all of our customers to check their DNSBL settings and remove any reference to the ORDB DNSBL.
DNSBL Settings can be checked by logging in to the GMS administration interface and navigating to Anti-Spam > Connection > DNSBL.
Keywords:ORDB DNSBL mail rejected