Knowledgebase

Someone got a message stating their email to me was blocked but it wasn't in my quarantine, why?

Scenario

Someone sends an email to you and they receive a message back similar to:

Remote host said: 550 http://www.spamcop.net/bl.shtml?0.0.0.0

Note: the 0.0.0.0 would be a real IP Address

Cause

This means that the email server used by the person who was unable to email you is on a block list because it's been sending SPAM.

We subscribe to a service (SpamCop) to check emails against known "bad" email servers which send SPAM. Sometimes legitimate email servers sometimes inadvertantly allow SPAM to be sent through and those servers end up on this block list. The big dogs (AOL, Yahoo, Google, Microsoft, et al) are usually able to get their servers removed from these block lists relatively quickly but while they are blocked, some email may be blocked.

Resolution

So, long story short, this should clear up in a few hours and the person who was trying to send to you will be able to again.

But why don't I see the message in my Quarantine?

Because when a server is on a block list, all messages from that server immediately rejected. The message never makes it to our filtering engine to be evaluated. This is done because generally all messages from a server on the block list are going to be SPAM.

Related Articles