Dany Petraska
By Dany Petraska |
IN Grow |

Spam Filters: Making Friends Out of Enemies

1600x600-making-friends-800x300You work hard to create emails that inform and engage your customers. You write, design, proofread, edit, and—proofread again. Then press Send. What happens? Some are bounced, some simply vanish. All that work, and still some email never gets delivered.

There are many reasons why an email does not reach an inbox. At PRI our goal is 100% delivery. We follow all CAN-SPAM rules and help our clients keep nice clean lists. But, though we can often tell if an email address is simply no longer valid, or an inbox is full, there are still undelivered emails. Why?

Spam Rules & Tools

Several “rules” are used to identify spam. These rules can be applied at various points along the path from hitting the Send button to delivery.

Where email may be caught:

  • The recipient’s email client (Outlook, Hotmail, Gmail, etc.).
  • Their employer’s anti-spam software.
  • Any additional software or programming (i.e., firewall) to protect that specific company, sometimes making it hard to send an email to our own clients!

Most companies have spam filters that examine incoming email that appears to be about the company itself but, because it did not originate from an internal source, the spam filter is automatically triggered.

Many of the individual anti-spam rules, by themselves, do not trigger spam filters (though some do!). Rather, an anti-spam program is looking for a combination of broken rules. This is why it’s important to remember that an anti-spam program is not a person reading and sorting through your email, it is a computer program. This means it “sees” your email linearly (from the first line of code, to the last). It does not appreciate your beautiful design, and could not care less about the perfect photo used to illustrate an idea. And, while it can’t “read” (other than searching for specific words/phrases) the big red headline you wrote to tell your customers about an awesome new product, it can calculate it: font size 40 + “risk free” + red = spam.

Play By the Rules

To know what to include and not to include, you'll need to monitor the continually evolving rules used by anti-spam programs (e.g., SpamAssassin). The rules are updated as spammers try and beat the odds—an ongoing, never-ending battle.

Most spam is very poorly coded, however, so simply paying attention to detail and using professionally designed emails, is a huge part of creating “safe” emails. But, because spammers attempt to imitate “real” emails to get through the spam filters, anti-spam programs not only filter out spam emails, but they also catch your legitimate emails. To illustrate how this works, the following is a sampling of some of the rules being applied to most emails:

Rule #1:

Look for the phrase “you do not wish to receive” or “you no longer wish to receive.”

What it means: We see this in all emails, even the legitimate ones. Opt-out instructions are, after all, required by law (see CAN-SPAM rules) and considered an email best practice.

What you can do: All you have to do is avoid these specific phrases, but that also means staying on top of these rules.

Rule #2:

Look for font tags, specifically font tags with a size of “+1” and larger and “3” and larger, and point sizes greater than “12.”

What it means: It’s looking for LARGE TEXT. Yes, you can use large text but use it in moderation, and in relation to other text, such as a headline followed by smaller text, then a subhead, etc.

What you can do: If your email message screams for a large headline, you can substitute an image of the text in place of actual text.

Rule #3:

Look for phrase “click here.”

What it means: Yep, that’s right. “Click here” can start the ball rolling on your email being considered spam. Why? How often do friends email you and write “click here”? (Never?) You can use a different phrase to get around this, or, at PRI we have begun to remove text asking to be clicked and instead, include a link from text that is more explanatory of the link and where it’s going. This is a good practice for two reasons: 1) to avoid email spam filters, and 2) better results for web pages in general for search engine optimization (not applicable to emails).

What you can do: Link from a descriptive word or phrase, example: You share your chocolate cake recipe with Caroline and she adds pureed beets that make your recipe even better.

Rule #4:

The link (URL) used in the unsubscribe copy includes an email address.

What it means: Long ago, before CAN-SPAM, all unsubscribe links went to an email address. With today’s double-opt-in subscriptions and automated removal (as opposed to an email asking to be unsubscribed, which then gets spammed out, and you never receive it!), the anti-spam rules reflect that most legitimate senders are using these tools. The rule is trying to discover the links/URLs being used to pass information back to a program (your information passed back to a spammer).

What you can do: Use an automated unsubscribe program.

Rule #5:

Font color is red, yellow, green, gray, blue, magenta, or cyan.

What it means: In other words, these are the colors that appear most often in spam emails. For each of these, it’s not all reds or all yellows, but a certain list of colors that can be coded using either the name or the hexadecimal code (i.e., “red” or “#FF0000,” “blue” or “#0000FF”).

What you can do: Avoid these colors, or use graphics if you really need to include a certain color (spam catchers cannot detect color in an image).

Rule #6:

Look for the phrase “risk free” and other related phrases, such as “no risk.”

What it means: This is just one rule, but there are several rules applying to various phrases, such as those already listed above, as well as: “free offer,” “special offer,” “trial offer,” “only $,” and more. Some rules look for EXACT phrases, and some do not. Some rules trigger being deemed spam all by themselves, and some do not.

What you can do: Stay up to date on which phrases are being tagged.

Rule #7:

Look for ALL CAPS.

What it means: This is an easy one to avoid since ALL CAPS are generally considered “yelling,” or “shouting” at the recipient. The anti-spam programs can tell the difference between ALL CAPS used as subheads, and ALL CAPS used in body text, but again, use sparingly, if at all. This rule also takes into consideration the use of many exclamation points or other punctuation around any ALL CAPS, as in: !!!WONDERFUL UNREALISTIC OFFER FORYOU!!!

What you can do: Avoid the over-enthusiastic use of exclamation points and words in ALL CAPS.

Rule #8:

Look for lame excuse about why the recipient is receiving the email.

What it means: Anti-spam programs look for phrases explaining why the email was sent, such as, “You have received this message as a member of our newsletter list.” Often senders are worried that the recipient won’t remember giving them their business card with their email address on it (or they didn’t actually ask to be added to any lists). But, while you don’t want any spam complaints, if someone was indeed interested in your company or product, they won’t need reminders as to why they’re receiving an email from you. As long as you give them a way to opt-out to future emails.

What you can do: Skip the reminders of why they are receiving your email, or better yet, come up with an original way to say it.

Overview and Best Practices for Your Email Campaigns

Even after reading this sampling of the rules that can send your emails into spam folders, or block delivery all together, there are really only a few simple strategies you need to follow:

  • Create clean, professional emails.
  • Never buy, borrow, or steal email lists or addresses.
  • Only use an email address you have used within the last two years.
  • Send only what you promised, and only as often as you promised.
  • Ask for permission.
  • Keep your emails informative and on topic.
  • Stay current on the latest spam rules to avoid obvious triggers.
  • Always include CAN-SPAM requirements: opt-out option; company name, address, phone; send from legitimate email address; etc.


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