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Aug 07, 2002
How To

Is Your Broadcast Email Being Filtered Before People See It? Top 5 Ways to Avoid Filters

SUMMARY: Why did this issue of SherpaWeekly arrive with [] brackets at the start of our subject line? Why do we spell words such as F^ree and S^pam funny?

It is all about avoiding email filters so that your issue gets to your in-box without being stopped along the way. If you are an email marketer or email newsletter publisher filters may be one of your biggest headaches right now.

This article includes top five tips for dodging filters, basic info on the two most common filtering methods, and some tech notes you can forward to the appropriate person on your...
The challenge today is how to make sure that the mail you send actually arrives in the inbox of the intended recipient. Two things are stopping it: Filters and blacklists.

We will talk about blacklists in a future issue. In the meantime, here is a quick primer on the two types of filters, plus five key tips on how to avoid being filtered out, and some useful tech notes at the end.

(BTW: You will notice what look like some typos in this article. They are on purpose, to stop us from being filtered. Read on for details.)

==> The two types of filtering that stop your messages

Filter Type 1: At the corporate level.

Many corporations use filters to check incoming mail. Either upon delivery or after its been delivered (AOL, for example, will leave you believing that your mail has been delivered, but it may be filtered into the trash before it arrives in the mailbox of the intended recipient). Filters, of which SpamAssassin is probably the best known, look at the headers, the contents of the subject line, and the contents of the message.

If you are being filtered at the corporate level, you probably do not even know. Unless your readers are aware enough (and care enough) to notice that they have not been receiving copies of your messages, you will never know. (** This is not quite true; the gory details are in the tech notes at the end.)

Filter Type 2: At the client level.

An increasing number of email recipients have implemented either their own inbox-filtering system (catching the most common offenders is easy). Using easy-to-configure rules, they automatically delete any messages that have particular keywords in them, such as F, letter after Q, EE or too many exclamation points, or the drug that Bob Dole promoted.

There are even desktop applications, such as MailWasher and MailShield that have the rules built-in, making it incredibly easy for average consumers to have 90-95% of incoming spam deleted without their intervention.

==> Top 5 Tips for Dodging Filters

This week we contacted the man who probably knows more about email than anyone else on the planet: John Buckman. or: How to Sell Subscriptions to Web Sites. Buckman wrote Lyris broadcast email software in 1994. Lyris is used to deliver 60% of all broadcast email sent by companies using commercial software. Your own broadcast email may well be delivered using Lyris. Because Lyris is so pervasive, many ISPs, blacklist providers, and filtering vendors consult with Buckman before they develop or modify their own systems. (Lyris also produces it's own enterprise filtering and desktop filtering products.)

"There is not going to be a silver bullet approach. Email is going to keep staying dirty," explained Buckman.

"The biggest trend right now is in filtering mail into different folders and prioritizing email. For people who open their inboxes to 200 messages, filtering is essential. They've learned to put mailing lists, which begin their subject lines with the list name in square brackets, into specific folders. You've got to get them to whitelist your messages so that your messages don't end up in a likely-s^pam folder, or worse."

Here are Buckman's top five tips for making sure your email does not trip a filter.

Tip #1

Send a welcome message when people opt-in, telling them how all future communications will appear, so that they can let your messages through their filters. Buckman suggests something like: "The message will come from, if you use filters, please add this address to your whitelist."

In an upcoming issue, MarketingSherpa will be providing you with detailed instructions (that you can share with your subscribers) on how to set up filters on your inbox and make sure your publication goes on the whitelist for the most popular email clients.

Tip #2

Do not send a "Crazy Eddie" marketing message. Spam filters pick this up right away, and you insult the recipient. Write in normal tones. Once you have an opt-in address, you do not need to yell to be heard.

Tip #3

Write all email ads that appear in your newsletter. (We can see this causing havoc with advertisers who want to maintain creative control though.)

"Newsletters without ads rarely trip filters. It's the ads in the newsletters that trip the filters because they read just like s^pam," explains Buckman. "The publisher should write the copy for the ads. The click through rate is higher when the voice is the same."

"Small businesses should make use of personal appeals to patronize the sponsor since that helps the small business out; people respond to that. One of biggest lists is Chicken Soup for Soul; they use that type of appeal all the time."

"People eat up that homey stuff," offers Buckman.

Tip #4

"Never use all caps or exclamation marks, especially in the subject line," suggests Buckman.

Tip #5

"People are now uniformly filtering in the subject line so put your trademark in square brackets in the subject line," encourages Buckman.

== Tech notes on filtering

Note #1

If you are publishing information about anything that might get filtered, then you should probably do what we have taken to doing: inserting strange characters into those words.

There is an epidemic of silence in the email-about-email publishing industry because those of us trying to inform and educate marketers and publishers are tripping the very filters we are trying to warn you about.

This is just a cat-and-mouse game with filters, at this point, but we have no alternative as long as filters are looking for these keywords. We suggest you adopt a similar approach.

Note #2

It is theoretically possible to know that you are being filtered if all of the following are true:

1. You are able to track opens by individual recipients

2. You know that recipients do not use Lotus Notes or Eudora to receive their email

3. You know that recipients are definitely interested in what you are sending.

If you publish a paid-newsletter, and you sell site licenses, and no one who is registered from a given (or multiple given) corporations is opening the newsletter, then you can be reasonably confident that there is corporate-level filtering going on.

You should know from your delivery report whether these messages are bouncing (and what the reason for the bounce), so you will be able to identify the problem as server-filtering or corporate filtering.

Most broadcast emailers will never know precisely which recipients are being filtered for at least one of the following reasons:

(a) will not have opens by recipient, let alone a history of opens for a given recipient,

(b) will not know what email client they are using; if they have been using Lotus Notes from the beginning, you will not have any record of opens ever, and

(c) you can not know whether the recipient is busy, uninterested, on vacation, on maternity leave, or never receiving your message.
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