Spam filters are at work at every level of the Internet, from ISPs to corporations to personal computers. We’ve all been annoyed by spam emails that are gibberish, or, worse, emails phishing for click-throughs to shady websites.
Unfortunately, perfectly legitimate marketing emails sent to opt-in recipients often get blocked by filters. Even mail between individuals can get trapped. For example, a copywriter sent a new client an email that contained draft text for a campaign. After the client complained the email hadn’t arrived, they discovered that the salutation “Dear friends” in the body of the message was enough trigger an over-sensitive spam filter in the client’s email program.
A few years ago, it was relatively easy to sail past spam filters simply by avoiding obvious mistakes (like attaching a Microsoft executable file or writing a subject line in ALL CAPS). But spammers, and spam filters, have become far more sophisticated. Some of the major commercial spam filters are updated on a daily basis to identify and block the latest wave of spam.
Ironically, much of the wording used by legitimate email marketing messages to comply with the federal CAN-SPAM Act has been mimicked by spammers, and now is used by spam filters to flag and block email. Direct marketing expert Ralph Wilson has even gone so far as to recommend that email copywriters look for ways comply with the federal requirement to include an “unsubscribe” mechanism without using the obvious phrases “to unsubscribe” or “removed from list” because those can trigger some spam filters and the message will never get through in the first place.
For the latest in spam-savvy email practices, check this list from the software company SpamAssassin of factors likely to get your email blocked. (The list includes some valuable, but highly technical tips, so be sure to share them with the person on your team who is coding your email.)
Finally, many direct mail marketers are including in their emails text urging recipients to add the sender’s “from” email address to their address books. (“Be sure to add our email to your address book so you won’t miss out on future offers!” is typical wording.) This guarantees that future messages will be recognized and get past computer- or company-specific spam filters.