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Sep 03, 2003

Are Bounces Lying to You? Beware: New Email Filter Tactic May Slash Good Names from Your List

SUMMARY: If you've noticed that more names on your list have "bad addresses" than usual these days, you're not alone. We found that about 5% of names on our lists are sending back false bounce reports. In effect, due to overzealous filters, thousands of people are being removed from lists without their knowledge or permission.

Share this article with your email broadcast techies and make sure they take it seriously. You work hard to grow your list - don't lose good names for bad reasons.

List owners already frustrated with the all-too-common problem of email filters stopping permission mail by mistake, now have a new problem to fret about -- bounce messages that lie to you.

Over the past few weeks, we've been deluged with reader complaints. Turns out that loads of people stopped receiving issues, and when they used our online account management form to figure out why, it told them they had been unsubscribed.

That's right - their names had been removed from our list without their permission.


Because we got a bounce report from their ISP or corporate IT department handling email telling us that their address was bad. That nobody used that email address anymore. The bounce report was lying to us.

There are more than 30-reasons why email may bounce, such as a full-mailbox. Broadcast emailers' systems have to sort carefully through all of them to decide which emails to leave on the list and which should be removed because the account has been discontinued completely.

While you never want to remove a name that's only briefly
unreachable, it's mission critical to remove completely
discontinued accounts immediately. That's because some major ISPs as well as AOL and Yahoo may filter out all of the mail you send them (even to good addresses) if they have evidence that you're repeatedly hitting bad addresses due to laziness about list cleaning.

In fact, you can lose white list agreement protection if you don't keep your list clean.

Your email system figures out which names to delete by reading the "Status" number in the bounce reply. If a bounce has the term "Status: 5.0.0" it tells the email sender "no account by that name" and if it says "5.5.1" it means "user does not exist."

However, we've discovered multiple examples of ISPs and corporate email departments who have begun recently to misreport this status. Whenever they discover something they think might be non-permission email, they send a 5.0.0 or 5.5.1 message to the sender even though the email address is still good.

Here's an actual example of a message (with email addresses removed for privacy) we got from the IT system of an MarketingSherpa reader whose address is perfectly good:

Message from their mail server:
Final-Recipient: rfc822;emailaddress
Action: failed
Status: 5.0.0
Diagnostic-Code: smtp;554 Your message has been blocked as part of our SPAM prevention system. If you feel you have been blocked in error, please contact emailaddress

Jim Tinney, CTO at TailoredMail, who handle our email broadcasts, says, "In this case, their server is responding to our mail server that the user does not exist (Status: 5.0.0) as part of their junk email block software, which is a sneaky thing to do. Only by going through and reading the messages [by hand] can you catch these."

In other words, it's currently hard-to-impossible for most
automated email broadcast systems on to figure out which 5.0.0s and 5.5.1s are lies and which are not.

How big is this problem? More than 5% of our list appears to have been affected, including email addresses from a wide variety of ISPs and corporations.

That's thousands of names that we would have never emailed again even though they were still good and definitely wanted to get issues from us.

Our four recommendations:

#1. Make sure you use an email broadcast service which is able to give you a bounce report with full details including the actual email reply from any system rejecting messages. Some programs and services only give you top-line numbers on bounces and not details.

While you don't have time to check every detail yourself for every send, you definitely need the ability to dive in to look at detail on demand when there appears to be a problem.

#2. Also make sure your reports separate out the names who leave your list by personal request versus auto-removes due to a bad address. Many systems lump these two very different groups together, which is a problem if you're trying to catch mistakes.

#3. Check your top-line bounce reports and number of names
automatically removed from your list on a regular basis to catch any blips that may occur. If you're bouncing or losing more names than usual, you should be able to catch it quickly.

Don't count on your email vendor to spot this for you -- you must routinely watch these numbers yourself.

#4. Contact your email broadcast firm and work out a plan to handle lying bounces. This may require some manual work for now.

As TailoredMail's Tinney says, "I think the only answer is to invest more time in personal, hands on list management - and to do some even smarter and more reactive things to examine and deal with bounces."

Our ultimate prognosis: the days when sending email was an ultra-cheap communication tactic are about to be behind us. Arrgh!
See Also:

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