Sometime mid last week, one of my clients--a state chapter of a national association--became unable to send to all of their AOL members. Assuming it was simply that AOLs servers were inundated with infected emails, I gave it some time. The errors were simply "delay" and "not delivered in time specified" errors.
AOL appear to have recently changed their MX receiving policies, see the following demon.announce post: http://groups.google.com/groups?selm=xVIP4XA5f7M%24EwzW%40demon.net&oe=UTF-8 &output=gplain --- cut here --- One such scheme uses a list of "end user" IP addresses on the basis that such users will only be sending legitimate email via their own ISP's "smarthost" email server. The idea is that the blocklist will be able to block non-legitimate email because it arrives directly. In particular it should block "spam" sent via insecure systems or virus/worm infections. We have recently been in discussion with AOL who are, at a future date, planning to implement just such a scheme as they have found, working with many ISPs around the world, that it significantly impacts their incoming spam volumes. --- cut here --- Regards, Jonathan