Navigating the Fiefdoms: Email Deliverability

Email. Everyone thinks it’s as reliable as the post office. “Neither snow, nor rain, nor heat, nor gloom of night, nor the winds of change, nor a nation challenged, will stay us from the swift completion of our appointed rounds. Ever.”

Wrong. Email is still subject to the hiccups and lost packets that the USPS subjects us to. Yeah, we won’t ever get an email that’s been kicked around, smashed, and tossed over the fence but sometimes, sometimes it just won’t arrive.

Wait, what’s that you say? It’s a computer! Nothing ever goes wrong with computers. Wrong again. We all have used the excuse on dear old Aunt Mabel about how we just didn’t get her email. The truth is, it happens all the time. The good thing is, there are steps you can take to make it less likely to happen.

Email marketing is inherently built on trust. I’m giving you my email address with the idea that I’m getting something out of it. Early access to information, deals, special offers, are usually the bait. In return, you are getting my money with the understanding that you are not going to sell my information to the highest bidder or spam the hell out of me with ten emails a day. I’m talking to you, Living Social and Groupon.

This is the best case scenario where the marketer has asked for and received your permission to email you. This would all be fine and dandy if there wasn’t a middleman. Your ESP. Google, Yahoo, heaven forbid, Hotmail, all have a giant wall around their fiefdom of internets.

As an email marketer, if you’ve ever taken a look at your bounce records, you may have had a time where you noticed there was an inordinate amount of bounces from from one particular domain. For example, in my experience it has been unbelievably difficult of late to crack Yahoo’s inbox for some senders, especially if you are sending from a new IP address. (Warming up an IP is a must, but that’s a talk for another post.)

So, what else can email marketers do aside from asking  new clients to add our sending address to their address book? In response to the never ending deluge of spam, there have been several standards that help to identify legitimate email. SenderID or SPF and DomainKeys or DKIM are, respectively, Microsoft and Yahoo’s forays into removing the processed ham product before it gets to your inbox. If you do a search for each of these you will find that there is a lot of confusion surrounding all of these standards. DomainKeys was created by Yahoo and DKIM was created by open source internet. There is a lot of conflicting information out there regarding these, but luckily for us, adding SPF records and DKIM records to your DNS will, for 90% of people, be plenty of identification.

So what exactly are these records doing?
DKIM Explanation in Japanese

No? Good, it’s not simple stuff. Essentially, SPF verifies your mail by checking the sending IP address against the address you specified in your DNS records. If they don’t match it’s off to the junk folder with your Viagra email.

SenderID Explanation


DKIM is a lock and key model like you see here. Your DNS stores a public “key” that can be accessed by receiving mail servers that will unlock the encryption that is added to your email’s headers when sent. If the key doesn’t fit the lock then your clients will never know how large their, ahem, bank account could be.

DKIM Explanation
Does this affect deliverability?

Yes and no. It is well documented that Yahoo, Gmail, AOL, and Hotmail use some combination of these identification options, along with IP reputation, and proprietary algorithms checking for spam indicators in deciding where to send your message. Enacting these measures does not ensure that your mail will be getting to its recipient but it definitely seems to help. You wouldn’t let someone in your house you didn’t know unless you could positively identify them right? Makes sense.

The other piece of this is sending email to a business that has their own rules, read firewall. I can’t tell you how many times I’ve worked with clients that have been sending email to a client forever and then suddenly the same email with no changes gets barred at the gates by the company firewall. It’s frustrating. Despite your best efforts in signing your mail with every manner of identification it’s still not making it. Thankfully, it is decidedly easier to improve the situation provided you have the ability to talk to their IT department. Usually the situation can be remedied fairly quickly by asking to have your IP or Domain whitelisted.

Email deliverability can definitely be a bit of a black box when it comes to the machinations of ESP’s. They have a reputation to uphold with their clients. Ultimately if you’ve enacted some identification procedures like DKIM and SenderID, are acting in good faith with the recipients of your material, and your material is something that the people want to read you will make it to the inbox. A good rule of thumb is to think about what YOU would like to have make it to your inbox and shoot for that.

About eROI

eROI crafts compelling digital experiences across email, web, and social channels. Our work has been consistently successful in driving revenue and exceeding goals for our partners.

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