Sunday, March 30, 2008

ORDB services no longer available

Few days back, some of your users might be getting this message (or something similar) when sending out mails to certain domains.

<>: does not like recipient.Remote host said: 550 5.7.1 has been blocked by ORDB-----------------------------------------------

Judging from the situation, it is very obvious that the sender was being blocked by the recipient site. But the actual situation is that the recipient site does still have configured at their SMTP server. ORDB is a public DNS blacklist service that was closed down in 2006 but their server was just removed on few days ago (around 25 March).

As a result of this, whatever valid emails that was sent to the recipient will be identifed as spam. To solve this issue, the recipient site will need to remove from their configuration.

So if you're not getting any mail, check your spam filter configuration!

History has announced that they will shut down their services after fighting open relays and spam for more than five and a half years. The RBL DNS service and mailing lists will be taken down today. December 18, 2006.