More on spamfiltering feedback

Al wrote a post commenting on my post from last Thursday on spamfilters talking to senders who are being filtered. I think his take on it is close to mine. I would point out that Google has a pretty opaque system and no feedback to senders, but a lot of people seem to think their filters are accurate and do a good job.
Overall, I think there is room for discussion and feedback between senders and recipients, but on both sides the goal needs to be improving the enduser experience.

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Troubleshooting a Postini block

Mail from one of my clients is being filtered at Postini and they asked me to look into this. Not that there is anything that can be done, of course. Even before they were bought out by Google, they were the poster child for a spam filtering company that believed they could do no wrong. It was difficult, if not impossible to get a straight answer from Postini about filtering, and the only statement they would ever make in regards to blocking problems was ‘have the recipient whitelist your mail.’
It is not just that Postini will not talk with people who are blocked, they will not talk to their own customers, either. Many years ago, I was dealing with another Postini issue for a customer. This customer was a Postini customer and was sending mail to themselves to test their new ESP. Postini was blocking the mail and the customer wanted me to find out why. After a couple days of digging I did actually find a really-o truly-o human at Postini. [1] He explained to me that a single line of text, followed by an unsubscribe link was spam, always spam and nothing but spam. He also explained that the only way for that mail to be let through, was for my customer to turn off his Postini filters.
Fast forward 4 years and I once again have a customer blocked by Postini.  Usually, I tell customers there is nothing to be done for Postini blocks and that no one can find any information about them, but this customer is insistent. This particular customer has extremely clean mailing practices, sends highly relevant and wanted mail and consistently gets 95+% inbox delivery. They are not spammers, not even a little bit. Because I know this customer is so clean, I poked around a little to find some information about them. They do use the ReturnPath Mailbox Monitor so I have a copy of the headers Postini is adding. I also discovered that Postini is now providing a decoder service for their headers at https://www.postini.com/support/header_analyzer.php
The response you get back from pasting in a header is not that useful if you have found any of the numerous explanations of Postini headers, but it does show some willing. Note, there is no way to ask a question or provide feedback to Postini on the listing.
There is not much that can be done to deal with Postini filtering your email. The best you can do is have your recipients whitelist you.
[1] I believe I am the only person on the delivery end that has ever been able to actually talk to a live human at Postini, and I think that is only because I called them from the same area code they are in and some engineer decided to return the message I left on their corporate voicemail.

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Affiliates: what is a company's responsibility

Many of my clients come to me when they end up with delivery problems due to the actions of affiliates. These can either be listings in some of the URL blocklists (either public or private) or escalations of IP based listings. In many of the cases I have dealt with affiliates, the affiliates have sloppy mailing practices or are out and out spammers.
Recently the FTC settled with Cyberheat over their liability for the behaviour of their affiliates. In this settlement Cyberheat is required to monitor their affiliates as follows:

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Yahoo and Spamhaus

Yahoo has updated and modified their postmaster pages. They have also put a lot of work into clarifying their response codes. The changes should help senders identify and troubleshoot problems without relying on individual help from Yahoo.
There is one major change that deserves its own discussion. Yahoo is now using the SBL, XBL and PBL to block connections from listed IP addresses. These are public blocklists run by Spamhaus. Each of them targets a different type of spam source.
The SBL is the blocklist that addresses fixed spam sources. To get listed on the SBL, a sender is sending email to people who have never requested it. Typically, this involves email sent to an address that has not opted in to the email. These addresses, known as spamtraps, are used as sentinel addresses. Any mail sent to them is, by definition, not opt-in. These addresses are never signed up to any email address lists by the person who owns the email address. Spamtraps can get onto a mailing list in a number of different ways, but none of them involve the owner of the address giving the sender permission to email them.
Additionally, the SBL will list spam gangs and spam supporters. Spam supporters include networks that provide services to spammers and do not take prompt action to remove the spammers from their services.
The XBL is a list of IP addresses which appear to be infected with trojans or spamware or can be used by hackers to send spam (open proxies or open relays). This list includes both the CBL and the NJABL open proxy list. The CBL list machines which appear to be infected with spamware or trojans. The CBL works passively, looking only at those machines which actively make connections to CBL detectors. NJABL lists machines that are open proxies and open relays.
The Policy Block List (PBL) is Spamhaus’ newest list. Spamhaus describes this list as

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