What You Should Know About Email Delivery

Editor’s Note: Today’s post is our monthly visit from a member of the Emma team. Emma is the email marketing provider for Social Media Explorer. Today’s post is from Art Quantstom of the Emma Delivery Team.

Technology adapts and improves at a dizzying rate, and if you neglect to pay attention for a moment, it seems you miss something really important. In some ways, this perfectly outlines what has happened with commercially sent email. Email Service Providers (ESPs) like Emma — businesses built in large part upon the service of simplifying the email process — take care of almost everything when it comes to delivering your emails, and it’s easy to take that for granted. But should you?

What if your email’s delivery doesn’t go as planned, and scores of subscribers miss out on your message? What questions should you ask your ESP’s support team to set things right? On the flip-side of that, what if they have questions for you about your email list, sending behavior or more? It happens, and you should be prepared to get technical.

The more you know about the delivery process, tips for satisfying spam filters and what you can do to keep your sending reputation high, the better. And building a relationship with your ESP’s support team can’t hurt either.

A brief overview of email delivery

Before we dig into some details about how to improve your email’s delivery, let’s back up and take a quick look at the SMTP (Simple Mail Transfer Protocol) transaction, since that’s where email delivery starts. SMTP has four main parts:

1. HELO or EHLO identifies the server which is trying to send mail to the server receiving that mail.
2. MAIL FROM identifies who is sending the email. This is your RSVP address.
3. RCPT TO identifies the email address you’re trying to reach. There’s one of these for every email you send to.
4. DATA is where you transfer the actual information — HTML, text, images — you’re trying to convey via email.

Each part can present its own unique challenges for delivery. More sophisticated mail transfer agents (MTAs) like Message Systems’ offerings and Port25’s PowerMTA can be extremely flexible in how they treat each part, and the most common issue is usually timeouts. Your MTA (or your ESP’s MTA) has max wait times set for each part of the SMTP transaction, and most domains’ response times fit well within these parameters. However, there are exceptions. Timeouts can occur at any time during the SMTP transaction, whether due to an unresponsive DNS entry, a mail server that is under high load or the specific settings for the receiving server.

The result? You’ll see emails that have soft bounced, and some legitimate recipients will miss out on your email message. If it’s a temporary issue, your MTA should be making multiple delivery attempts within a 24-hour period, and on one of the subsequent attempts, your email will be delivered with no adjustment to the MTA’s settings.

But, if the timeout is the result of particular settings on the receiving server, you’ll need to work with your ESP and figure out which piece of the SMTP is timing out, what your wait time settings are currently, and, if possible, exactly what your settings should be for the domain in question. Many people aren’t aware that changes can be made to the MTA — or aren’t willing to take the time to diagnose the problem — but once you’ve discovered the specifics, it keeps your emails delivering smoothly.

What about spam filters?

So let’s say that your emails are being delivered successfully to the receiving server. That’s good, but now you’ve got to take spam filters into account. Filters like SpamAssassin and Postini, as well as offerings from Barracuda and Symantec, are pretty common. They all look relatively similar on the outside, but can vary quite a bit in how they act toward your emails. And for good reason. They have the unenviable task of weeding out all of the bogus mail that tries to make it into your inbox every day. There are so many spam filters, in fact, that there’s no way to please all of them. Not 100%, anyway. Instead, follow a few basic rules to ensure your emails have the best chance of reaching the inbox:

1. Ask your recipients to add your “from address” to their address book or trusted sender list. The more apparent your relationship is with your recipients, the less likely you are to be filtered.
2. Authenticate your emails. Update your organization’s SPF record. Ask about DKIM and how that can be implemented, too.
3. Be consistent with the appearance of your mailing: no super-sized images, widely varying font sizes or unnecessary formatting. Above all, never let bloated formatting overshadow your message.
4. Learn from your spam folder. Take a look at the emails that get filtered there to find out what you’d be best to avoid. Large fonts, anything in all caps, sensationalized claims, calls to action — these are all trouble.

Is that it?

Not quite. How your recipients react to your emails is another important aspect of your success as a sender. Trends in bounce rates, opens, click-throughs and opt-outs provide insights into what you’re doing well and, maybe more importantly, what you’re not.

For a list that is relatively static, meaning you’re not adding a significant amount of recipients between mailings, your bounce rate should be static as well. If you see it trending higher, or if you see an erratic jump, you’ll need to look into it, as you may need to adjust your MTA or do some work to repair your sending reputation.

For opens and clicks, you’d like to see them trend upwards, but don’t scoff at a steady 25% open rate or 6% click-through rate, either. Clicks can be fickle, depending on the campaign design and purpose; not every one is driving traffic to other places. If you see a drop in open rates, consider taking action. Ask your ESP’s support team for advice, and educate yourself on ways to improve open rate.

If you’re seeing a consistent single-digit open rate for every campaign, it’s pretty likely that your email list needs some clean-up. It’s also likely that your emails aren’t making it to the inbox at all. It’s not a lost cause, but you do need to take steps to repair your reputation. Send a re-engagement campaign to get people back in the fold; it can do wonders for a low open rate. Moreover, remove recipients from your list who are not engaged. These folks are more likely to opt out and complain anyway, so trimming them will give a quick boost to your sending reputation. (Read more about your online reputation on the Emma blog.)

Speaking of complaints and opt-outs, make sure you’re monitoring them closely. When I say complaints, I don’t mean direct emails to abuse@ aliases (although those are important, too). I’m referring to complaints that are sent back to your provider via Feedback Loops operated by many of the larger Internet Service Providers. These complaints, when out of proportion with the amount of mail sent, can cause your email to be filtered or outright blocked. Your ESP monitors these complaints and might reach out to you to have a conversation, should there be a problem. Even though you may not have access to the complaint data for your mailings, you can do the following to stay ahead of a potential problem:

1. Watch your opt-out rate. It should be pretty low: less than 0.5%. If that number creeps or bounds up to 1%, start asking questions. What changed with your audience? Did you run a contest, acquire a new list or change your mailings significantly? If not, how old is your list? It might be time to re-engage.
2. Watch your open rate. If it’s stuck in single-digit territory, it’s likely that complaints have been consistently high over time. Re-engaging your list and removing unresponsive recipients would be a great starting point, as mentioned above.
3. Grow your list responsibly. Never rent or purchase lists. Run promotions and giveaways, but make sure they’re relatable to your brand and message. Don’t give away an iPad if you sell cookware. Don’t give away cookware if you’re selling computers. If you acquire or merge with another company, let the new customers know first before you assume that the list is yours. Remember, they never really signed up to receive messages from you. Ask for permission.

If you do all of this, you should be well on your way to creating and maintaining a healthy, happy email list.

I know it’s a lot of information, but I hope it’s helped to clarify the delivery process — and what you can do to keep your emails chugging along. Luckily, your ESP takes care of most of it, and with a watchful eye and the right information, you’ll be able to manage the parts that are within your control. Failing at any part of the process could (and probably will) catch up with you in time. In that case, make corrections, rebuild trust with your recipients and enjoy better delivery going forward.

As a member the delivery team at Emma, Art Quanstrom keeps an eye on our sending reputation. After hours, he can be found playing drums in Nashville and searching for the best bowl of Pad Thai.