Why Are We on E-mail Blacklists?

LogicallyRogue asks: "I run an email server for a small webhosting company. We've crawled all around the email server to make it as secure as possible: tightened Sendmail's security, POP Before SMTP, denying non-authenticated relaying, using SpamCop DNS blacklist, etc. However, with all this in place, every few months, it seems that we have been blacklisted by some ISP somewhere. This month it was AOL. We had no warning, and we don't know why we were blacklisted. All the information we have is a single URL. We visit all the DNS blacklist services we can to be sure we are not on any of them. We send emails to the postmasters inquiring for more information (like perhaps a reason or copy of the email that made the ISP blacklist us) - however, those are usually bounced back because we are blacklisted. We've tried calling the Blacklisting ISP tech support - and usually get the stunned I-have-no-clue-what-you-are-talking-about silence. Have any other Slashdot readers experienced similar problems with blacklisting and the big ISPs?"

Comments

RBL's aren't perfect...

[PunkeyFunky]

..and as such, shouldn't be relied upon as a "oh this is definately for rejection". My firm uses an RBL as a plug in to SpamAssassin. Just being in the RBL by itself isn't enough to get rejected, but it bumps up the score a bit. Unfortunately, because RBL's are easy to slave and use, too many people rely on them, when the use is now limited. Limited by the fact that the 'big' spammers are incredibly clever these days. Having said all that, it wouldn't surprise me if AOL started blocking addresses with the '@' symbol... ;) Lee -- 'I love spam. Come get me.'