12 Ways to Improve Email Deliverability
You spend a lot of time creating your email marketing campaigns. It would be sad if some, or even many, of them didn't arrive at their intended destination because of an arcane little "gotcha" in the world of email deliverability. Here are the most important things to keep in mind.
Steps You Can Take
1. Optimize your subject line. Here are a few don'ts to consider when writing subjects:
2. Turn open-tracking off (also known as read-tracking). Turn off read-tracking. Some spam filters block emails if they contain a "web bug". A web bug is the invisible unique image ESPs place within eacgh HTML email to provide their customers with open-tracking reporting capabilities. For higher deliverability, send your emails without open-tracking.
3. Send HTML and plain text together, instead of just HTML. If you're sending HTML messages, make sure to also include a plain text alternative for those email readers that support HTML. The reason for this is because spam filters will flag a message as spam if it contains an HTML message but no plain text alternative.
4. Calculate your spam score. Before you send your email, use a spam checking utility to determine your spam score. Many of these tools use the SpamAssassin engine to "score" an email for spam content. SpamAssassin is the world's most popular spam filtering software, and it performs over 1,200 tests on an email message. For each test that an email fails, a score is assigned. If the total score is above a certain threshold (usually 5 points), then SpamAssassin classifies the message as spam, and we recommend you make adjustments to your email to get the total score under 5 before you send it out to all of your recipients.
5. In HTML emails, use a word or phrase, rather than a URL, as your hyperlink. Phishing scams are emails sent to a user falsely claiming to be an established legitimate enterprise in an attempt to scam the user into surrendering private information that will be used for identity theft. The email directs the user to visit a web site where they are asked to update personal information, such as passwords and credit card, social security, and bank account numbers, that the legitimate organization already has. The Web site, however, is bogus and set up only to steal the user's information.
Some email clients come equipped with a phishing scam detector. Most phishing detectors work by looking for a hyperlink within the HTML portion of the email where the link display text is an actual URL, but is a different URL than from the hyperlinked URL. When using click-tracking, email service providers modify the destination URL, so it is important to use a word or phrase as the display text rather than a URL, since the display URL will not match the hyperlinked URL.
6. Respond to Challenge Responses. One spam filtering technique is called challenge-response. Challenge-response filters send a reply email back to you asking you to click a link before the email that you sent is delivered to the recipient. This verifies that a human being actually sent the email. After this process, your From Email Address is white-listed with the recipient, so that future emails sent to that recipient won't generate a "challenge".
7. Publish a Sender Policy Framework (SPF) Record. Make sure the domain from which your email will be sent have published SPF records within their own DNS servers. Your ESP should be able to assist in the composition of the appropriate SPF records. For more information on SPF, please see http://spf.pobox.com.
8. Sign email campaigns with DomainKeys/DKIM. Your ESP should provide the tools to and instructions for you to set up DomainKeys/DKIM for your own domain.
DomainKeys Identified Mail (DKIM) is another DNS-email key-message system for associating a domain name to an email message, thereby allowing a person, role, or organization to claim some responsibility for the message. The association is set up by means of a digital signature which can be validated by recipients. Responsibility is claimed by a signer, independently of the message's actual authors or recipients, by adding a DKIM-Signature field to the message's header. The verifier recovers the signer's public key using the DNS, and then verifies that the signature matches the actual message's content.
Prominent email providers implementing DKIM include Yahoo, Gmail, AOL and Fastmail. DKIMis the result of merging DomainKeys and Identified Internet Mail. Visit the DKIM homepage for information on implementing DKIM for your domain.
9. Respond to each spam complaint individually. Even though you are sending legitimate emails that conform to anti-spam policies, that doesn't mean that recipients don't complain. Sometimes a recipient may forget that they signed up for a particular list. Therefore, all spam complaints that are reported to you or your ESP should be responded to individually. Compose a response to the complainant . Often times, after this process, you will receive an apology from the complainant. This ensures that you maintain an honest, clean, and high-integrity relationship with the Internet community at large.
Steps Your Email Service Provider Should Take
1. Participation in whitelist programs. Your ESP should participate in all major whitelist programs to help ensure its customers' emails are delivered to their recipients' in-boxes. These include negotiating whitelisting agreements with AOL, Yahoo, GMail, cable and telephone companies as well as third-party whitelisting programs such as Ironport's Bonded Sender program.
2. Stay off email blacklists. A controversial, yet still widely used method of spam filtering is subscribing to one or more publicly available email blacklists. Blacklists contain IP addresses of companies that are known to have a record of spamming. Make sure your ESP and its email servers are not blacklisted anywhere, and that they take proactive measures to ensure that we maintain an excellent reputation with blacklist operators.
3. Email server log file monitoring. Your ESP should use a special log file analyzer to monitor its email server log files for failed deliveries. This analyzer generates a daily report to our network administrators, who can then determine if there are any domains rejecting their email. Sometimes domains inadvertently block email from networks that generate too high a volume of email, even when the email isn't spam. When your ESP is proactively monitoring its log files for these types of blocks, it can react almost instantly by contacting the appropriate email administrator to remove the block.