There’s a common bounce error from the Message Labs’ filtering appliance that goes no where.
501 Connection rejected by policy [7.7] please visit www.messagelabs.com/support
If you’re trying to troubleshoot a delivery problem and you find any reference to www.messagelabs.com/support, try http://www.symanteccloud.com/supportcentre/information/r_troublshooting instead. That link provides a little more information.
Earlier this week some ESPs started asking if other ESPs have seen an uptick in Spamcop listings. The overwhelming answer (9 of 11 ESP representatives) said yes. I’ve also had clients start to ask me about Spamcop listings. All in all, there seems to be some changes at Spamcop that means more senders are showing up on the Spamcop radar.
Luckily, Spamcop provides us some insight into their data processing. If you look at the current monthly volume graph, we can see some very interesting changes in data.
A lot of filters started out just as filters against spam. But over the years they’ve morphed into more general blocks against dangerous or problematic email. There’s a lot of crime and bad behavior on the internet, much of it using email as a conduit or vector. Filtering is so much more than stopping spam now. It’s as much, or more, about stopping crime.
Email filters are essential to protect us from scammers. Sometimes I forget this, and then I read about a grandmother getting swindled by a Nigerian scammer and ending up dead.
There are real consequences to poor filtering and there is real crime facilitated by email. It’s easy to forget this as we deal with the email that gets caught in filters when they shouldn’t.
Filters are one of the first lines of defense against online crime.
Not only does filtering stop crime, but they also keep email working. An unfiltered mail stream is an ugly, unreadable, unworkable mess.
Yesterday I wrote about the underlying philosophy of spam filtering and how different places have different philosophies that drive their filtering decisions. That post was actually triggered by a blog post I read where the author was asking why Gmail was using the PBL but instead of rejecting mail from PBL listed hosts they instead accepted and bulkfoldered the mail.
The blog post ends with a question: