Email Deliverability Guide (part2)

TMO Group TMO Group

SECTION4: Authentication: Secure Your Identity and Make the World Safer

Email authentication has a proven track record but a surprisingly high percentage of businesses still haven’t implemented it. Authentication is an “ID check” for your mail streams: it validates that the email is actually from you (and not some spammer impersonating you). Authenticating your mail streams does not ensure your email will be delivered but it helps ISPs to further differentiate your business from spammers and other illegitimate senders. As fraudulent “phish” emails and other deceptive practices endanger consumers and businesses, authenticating your email is one positive step you can take today to make the [email] world a better place. Strong reputation metrics combined with properly implemented authentication can significantly improve your chances of reaching the inbox. If you’re sending transactional email, it’s even more important since your customers are expecting and anticipating those messages.

How does authentication work? How do I get started? There are three accepted methods of authentication: Sender Policy Framework (SPF), Sender ID and Domain Keys identified Mail (DKIM). The best practice is to implement all three methods, especially if you have high-volume transactional email streams. Here’s what you need to do to get started:

Step 1: Get details on the various types of authentication – implementing all three standards is the best practice. You can find detailed information on the following websites:

DKIM: http: // www.

Sender ID: http :// .com/senderid

SPF: http: //

Step 2: Take stock of all systems that send your mail. Identify all machines that send mail for your company. Next, determine the IP addresses (if you’re planning to use SPF or Sender ID) and sending domains used.

Step 3: Create your authentication records. There are excellent online tools available for Sender ID, SPF and DKIM.

Sender ID: http :// /senderid


DKIM: http: //

Step 4: Publish your authentication records. If you are using SPF, Sender ID or DKIM, work with whoever manages your DNS records to publish the email authentication records you’ve collected. The actual publishing is easy; finding the responsible party who controls your DNS may be the tricky part.

Step 5: Set up your mail server to sign outbound email with DKIM. DKIM requires that your MTA have the appropriate software implementation to sign all outgoing emails. Learn more at:

http: //

Step 6: Test your authentication records. SPF, Sender ID, and DKIM provide options to publish your records in “test” mode. This provides the opportunity for testing without risking delivery failures. The following resources can also help you test your DKIM signed messages:

SECTION5: Your Emails: Five Basics to Keep Your Reputation Intact –and Your Members Happy


A good reputation also means that only a small percentage of your emails “bounce” back or are returned by the ISP because the account is no longer active (hard bounce) or the mailbox is temporarily full or the recipient is out-of-office (soft bounce). If a lot of your mail is bouncing back, it means your subscribers aren’t engaged and you’re not keeping up-to-date with them. It also indicates that your list hygiene practices are not up to industry standards. Sounds like a spammer? Looks like a spammer to an ISP so your email isn’t going to get delivered. Keeping your bounce rate low by implementing procedures to immediately remove “hard” bounces is essential.


A clean, well-managed subscriber list can be your best asset, whereas “dirty” lists with out-of-date information are a leading cause of deliverability failures and are sure to damage your sending reputation.

List hygiene is the process of removing “bad” addresses in a timely manner. Good list hygiene practices are essential to avoiding spam traps and keeping your bounce rates low – key drivers of your reputation. There is no better way to assure consistent deliverability success than by regularly cleansing your

list of hard bounces, unknown users and other inactive addresses. SendGrid’s real-time Event API is a great start, providing instant information like opens, bounces and unsubscribe requests for individual subscriber records.


Welcome messages are the cornerstone of a well-run email program. When was the last time you signed up for a new online service and didn’t receive an immediate message confirming the sign-up?

Welcome messages (like other transactional emails) are more than confirmations: they’re an opportunity to engage with subscribers and start the relationship off on the right foot.


Complying with the federal CAN-SPAM law is not difficult. The requirements are straightforward and most legitimate programs were adhering to these standards long before they were legally required.

Here’s what you need to do:

l   Have a working unsubscribe mechanism in the footer and/or header of all email communications. Alink to your preference center is also a good idea, but make sure the removal can be done in a few clicks.

l   Include your official business street address in the footer of all email communications. This should be your corporate headquarters or another address where official communications are handled. It cannot be a PO Box.

l   Handle all unsubscribes requests within 10 business days. This means when someone asks to be removed from your list, you must suppress that email address from future mailings within 10 businessdays. This is the minimum, and ideally the suppression should occur within 24 hours.


It sounds obvious but it’s actually harder than it sounds. There is no secret formula to sending emails that work. First, make sure you’re following the four suggestions outlined above. Second, the content of your emails needs to be relevant, interesting and aesthetically aligned with your brand. Ask yourself some basic questions before you hit “send”: Will my subscribers want to read this email? Does the email look good? Is it a positive reflection of my brand? Overall, am I getting the right message to the right subscriber at the right time?

Edit by Lily HONG

Subscribe to our newsletter

News of the eCommerce world, best practices to use in your eCommerce platform, insights and analytics of Chinese and South East Asian eCommerce markets - all that and much more in our monthly newsletter.