The Email Standards Project launched last week. This group is looking to lobby and encourage companies to make their email clients comply with HTML display standards. They are also identifying how different clients display email with HTML. Check out their website, and see what they’re doing.
I do apologize for the light blogging recently. I have a couple big deadlines on my plate. I hope to get back to regular blogging soon.
The recent layoffs at AOL did affect the AOL Postmaster desk, and information I have received is that there was significant loss. As a result of the staff decrease, some changes have been made to the whitelisting and FBL processes. In order for a FBL to be approved it must meet the new FBL guidelines. In a nutshell, anyone wanting to get a FBL from AOL must meet ONE of the following criteria.
Read MoreA number of groups provide tools for monitoring email performance.
Some of these tools are provided by ISPs, like Hotmail and AOL have postmaster webpages. Hotmail also provides things like SNDS so you can monitor what Hotmail is seeing about your network.
Al has a new blacklist stats center over at DNSBL.com. Of interest is the accuracy of some of the widely used lists like Spamhaus, Spamcop, and PSBL. Other lists like FiveTen were wildly inaccurate. In fact, Al has shown that blocking mail from any IP with a 7 in it is more accurate (more spam hits, less non-spam hits) than FiveTen.
ReturnPath provides free reputation lookup and monitoring based on the data they acquire.
Over the last couple days multiple people have asserted to me that Yahoo is greylisting mail. The fact that Yahoo itself asserts it is not using greylisting as a technique to control mail seems to have no effect on the number of people who believe that Yahoo is greylisting.
Deeply held beliefs by many senders aside, Yahoo is not greylisting. Yahoo is using temporary failures (4xx) as a way to defer and control mail coming into their servers and their users.
I think much of the problem is that the definition of greylisting is not well understood by the people using the term. Greylisting generally refers to a process of refusing email with a 4xx response the first time delivery is attempted and accepting the email at the second delivery attempt. There are a number of ways to greylist, per message, per IP or per from address. The defining feature of greylisting is that the receiving MTA keeps track of the messages (IP or addresss) that it has rejected and allows the mail through the second time the mail is sent.
This technique for handling email is a direct response to some spamming software, particularly software that uses infected Windows machines to send email. The spam software will drop any email in response to a 4xx or 5xx response. Well designed software will retry any email receiving a 4xx response. By rejecting anything on the first attempt with a 4xx, the receiving ISPs can trivially block mail from spambots.
Where does this fit in with what Yahoo is doing? Yahoo is not keeping track of the mail it rejects and is not reliably allowing email through on the second attempt. There are a couple reasons why Yahoo is deferring mail.