The short version is that an online special interest group noticed that they were having issues with mail not being delivered when sent to Comcast addresses. They then worked their way though the Comcast abuse department to finally find that Symantec’s Brightmail was filtering on their domain name and identifying all their messages as spam. The cause for the block? 46,000 complaints filed against messages that contained the domain name of the special interest group. Symantec, once contacted was quick to remove the domain from its filters.
There’s a few lessons to be learned here about filtering and deliverability, first let’s look at …[Read more]