Host: Lauren Meyer, VP of Industry Relations & Compliance at Kickbox
Guest: Tamara Bond, Delivery Operations Manager at dotdigital
Meet Tamara Bond
Tamara is dotdigital’s Delivery Operations Manager and mail-server-tinkerer in chief. With over 7 years experience in bulk email delivery specifically, as well as a depth of knowledge in more general digital marketing & SaaS technology, she brings plenty of expertise on data-driven development, quality products, and taking a scientific approach in figuring out how stuff works.
She is also involved with anti-abuse and collaboration efforts both at home and in the wider industry and email ecosystem.
How Senders Become Aware of Deliverability Issues
Reaching the inbox isn’t as straightforward as we might hope. Whether technical or data-driven, there are a myriad of reasons why your email might not make it to the intended destination. And when deliverability issues occur, it can be a less-than-pleasant experience. Some of the most common ways senders become aware of a deliverability issue are:
Reduction in performance. This can be identified within their email engagement metrics (i.e., reduction in delivery rates, unique opens, or number of clicks-throughs) or campaign performance (i.e., conversions, revenue per email).
Report from a recipient. These reports can come from customers (or your CMO) complaining about emails going missing or ending up in their spam folders. They can also be sent to your ESP’s Abuse Desk, advising of issues such as a broken unsubscribe link or receiving unsolicited emails.
Compliance investigation. If the Abuse Desk is receiving complaints, or your sending activity results in poor results (i.e., high bounce, unsubscribe or complaint rates), it can raise flags with your ESP’s compliance team. Believe it or not, their goal is genuinely to help you improve your performance, even though their assistance might involve a rate limitation or other type of restriction on your account.
Deliverability monitoring tools. You may be notified of an issue with sender reputation, authentication, blocklist activity or spam trap hits by your ESP’s performance dashboard or by receiving a real-time alert from a 3rd party tool such as Kickbox’s Deliverability Monitoring Suite.
Once you become aware of a deliverability issue, it’s important to understand why it’s happening before you can figure out how to fix the problem.
Common Reasons Senders Face Deliverability Issues
So you’ve identified an issue with inbox placement, but what gives? There are a lot of possible reasons for getting sent to the spam folder or having your mail blocked, but some of the most common ones include:
Data quality. Most deliverability issues can be boiled down to a problem with the data. Some mailing lists have been collected without permission, while others suffer from list hygiene issues caused by not removing addresses that have hard bounced, unsubscribed or marked an email as spam via a feedback loop.
Subscriber management. Consistent inbox placement requires senders to take care of their mailing list from the point of sign up, all the way through to when a recipient has unsubscribed or otherwise been removed from a list. Marketers must regularly analyze their email metrics to better understand their audience and improve targeting/segmentation, as well as to perform regular list hygiene.
Lack of a holistic approach. If an email program or mail stream doesn’t have well-established goals and a clear way to measure success, it can lead to misinformed tactics such as chasing high open rates when your goal is really to drive more conversions. In order to optimize the recipient experience (and your deliverability) consider the macro and micro view: stepping back to see the whole picture, but also focusing in on the granular details of how you’re collecting and managing data, what kind of content you’re sending, what kind of data you’re collecting about subscribers and how you’re using it to improve your targeting.
Engaging in “Business as Usual.” Email is constantly evolving, and subscriber needs change over time. Stagnation within an email marketing program can lead to sub-par results because it’s quite possible that what worked yesterday won’t still work tomorrow. Outdated sign up forms or collection practices that don’t identify invalid addresses or protect against bot signups, sitting on data you’ve been collecting for 15 years without adjusting targeting, and sending the same offers too frequently are just a few examples.
Skipping fundamental steps. There are hundreds of factors that go into determining if your message will be delivered to the inboxes of your recipients or not, but making it clear who you are as a sender and establishing a positive sender reputation can go a long way to having your emails to be delivered. If a sending domain is lacking SPF/DKIM authentication or if too much volume is sent through a new domain or IP without warming it up first, mailbox providers (MBPs) will question whether what you’re sending is legitimate. This can lead to delays in delivery, spam folder placement, and even messages being blocked outright.
Resolving Deliverability Issues
Challenges with inbox placement rarely just go away on their own. Once you’ve identified a potential problem, you’ll want to take action quickly to ensure that snowball of an issue doesn’t turn into an avalanche.
There are many directions a deliverability investigation can take you, so we’ve outlined a few key questions and data points you should review, in addition to your email metrics, as a starting point.
Find out what’s causing your deliverability issue.
Because deliverability issues could be tied to so many possible reasons, it’s important to have a workflow of questions to ask to help you navigate those “uh oh” moments. You may not have the answers to all of these questions, but try to collect as many facts as possible to have a better understanding of the scope of the issue you’re facing.
How did you discover your issue? This question can help you understand how widespread your issue might be and give clues as to how to solve it.
- Are customers (or your CMO) complaining about emails going missing or ending up in their spam folders?
- Did your seed test results indicate mail was ‘missing’ or being delivered in the spam folder?
- Are you seeing bounce messages? If so, what do those say? We dig into what email bounces tell you about your deliverability issue in greater detail below.
What specific issues are you seeing, and where? Is it affecting just one recipient or many? Did you notice a drop at one particular mailbox provider or multiple?
The path to investigating and resolving a block with a MBP will look different than if you’re dealing with a spam folder issue. And the strategy might change if you’re facing an issue at Gmail vs. Hotmail vs. a regional destination in France or Germany.
All of these MBPs have a similar goal in mind, which is to deliver only wanted mail to their users inboxes… and to block the rest. But the way they define “wanted” mail is different. And the way each of them filters spam and phish, the patterns and metrics that matter to them the most, the sophistication in their filtering… all of that tells us something about what’s driving the issue.
When did it start? Note that we’re not asking when you identified the issue here. By identifying when you actually start to see performance declining, you can determine where to start looking for the root cause of the issue. Whether it has just started, or if it’s one that has persisted for months, you’ll want to take a look at the period a few days prior to when it began to determine what might have changed around that time.
Did you change anything around the time the issue started? Have you updated your authentication, introduced new lead sources, changed your content or modified your segmentation recently (i.e., to remove or include ‘inactives’)? Consider large and small changes here.
Are there any compounding factors? In one way or another, most deliverability issues stem from sending emails to people who don’t want to receive them: either they didn’t sign up in the first place, or perhaps they did sign up but don’t remember doing so. Other times, the content isn’t what they expected, and the process to unsubscribe is too complicated, so they mark your email as spam instead. All of these things are bad for deliverability, so it’s helpful to ask questions like:
- How do addresses end up on your list? What are the address collection sources?
- What was the lead magnet that brought them there?
- What expectations have been set about the kind of content recipients will receive, and how often will they’ll receive it?
- How often do you email recipients, and when was the last time you contacted them?
Test the program yourself. Some deliverability investigations uncover the fact that what marketers think is happening with their sign up process or automation series is not working as expected. Testing out the experience of new subscribers to see what happens after hitting ‘Submit’ can reveal potential issues with data collection or management that aren’t super obvious within your data but are negatively impacting your recipient engagement and inbox placement.
- Is a welcome email sent? How quickly after signing up, and what does it look like? What does it tell the subscriber about what’s to come?
- Does your brand send the content you promised? Do you send any content that a subscriber wouldn’t be expecting?
- How often do you contact your recipients?
- Does your unsubscribe link work? Is the unsubscribe process clear and easy to follow?
Take inventory of bounce data.
Bounces are emails that haven’t been delivered. They can occur in two places:
- During the SMTP transaction (“synchronous”) – bounces that happen during the initial transmission between the sending server (you) and the receiving server (i.e., Gmail, Hotmail).
- Asynchronous bounces that happen afterward – in this case, the receiving server tells you the email has been received, and then later sends you a message to say, “nevermind, we didn’t accept this.”
Most ESPs only break bounces down into two types (hard and soft), but there are actually three main classifications of bounces to be aware of:
Hard Bounces (5xx error code): these normally point to a permanent problem such as “this mailbox does not exist” and should not be contacted again.
Soft Bounces (4xx error code): These tend to be temporary issues such as this person has gone on holiday and their inbox is full. Or maybe your MBP is telling you they won’t accept the mail because you’re on a blocklist.
Deferrals: These are interim bounces that happen during the SMTP transaction, where the recipient server (i.e., Gmail) is telling the sending server (you) to try again later. This can happen because the recipient server is overloaded at the moment or because the emails you’ve sent recently are bad enough that they need you to slow down how much you’re sending. The majority of ESPs are already configured to retry deferrals (typically for 24-72 hours), but they can result in a hard or soft bounce if they persist beyond that timeframe. In those cases, refer to the 4xx or 5xx code for more information.
Most MBPs send mail to the spam folder first, so if you’re at the point of getting blocked, your issue has either persisted for a while (and might take longer or more positive changes to solve), or you’ve done something quite bad to get blocked “out of nowhere.”
Ignoring bounces is a surefire way to damage your reputation. For example, sending to a lot of addresses that hard bounced because they don’t exist is a problem because it suggests to MBPs that you aren’t getting consent from people before emailing them. Ignoring soft bounces can also be damaging because these are a signal of an issue with sender reputation or a MBP who is telling you to slow down. Continuing to send will only exacerbate the problem.
Keep in mind that bounce codes are NOT standardized. Sometimes a 5xx code is returned when it’s a temporary problem, or a permanent issue will come back with a 4xx code. Similarly, there is a lot of variety in the content of the bounce messages themselves.
Some MBPs have bounces that are very explicit (such as one that tells you your IP is on a specific blocklist), whereas others are totally vague, and you need to trust that the 4xx or 5xx is informing you correctly. So, review your bounces with a discerning eye, and check with your ESP if you have any questions.
Use spam trap activity to identify list collection & management issues.
A spam trap is an email address used to identify senders with problematic list collection and/or maintenance practices.
Spam trap networks can be run by anti-abuse providers (such as Spamhaus, SpamCop and SORBS), or they can be associated with deliverability vendors and ESPs who are using them for monitoring.
There are several different types of spam traps that you should be aware of, each highlighting a different type of issue that can affect inbox placement:
Typo traps are created when someone purchases a common typo domain (such as gmial.com) and sets it up as a trap to identify email senders who have issues with data collection. Moving from a single opt-in (SOI) to a confirmed opt-in (COI) process, and/or implementing real-time verification at the point of sign up, can help you confirm that an email address is valid before adding it to your mailing list.
Recycled traps are old domains or email addresses that were once active but have since become invalid due to inactivity or because the owner closed their account. When attempting to send to one of these addresses, the initial result (for at least 6-12 months) would be a bounce response from the MBP, telling you that the address does not exist or is no longer receiving messages. After that period, the address becomes “live” again, but now it’s a recycled spam trap, helping to identify problematic list maintenance practices. If your brand hasn’t sent any emails to an address for more than 6-12 months, consider that it could leave you vulnerable to hitting recycled spam traps. It’s not great for the recipient experience, either.
The best way to resolve an issue with recycled traps is to target active recipients who have very recently signed up, or who opened or clicked an email from you within the past 3-6 months. The logic here is that the majority of reputable spam trap operators don’t open emails, so by suppressing inactives, you can effectively remove most of your spam traps.
The best way to avoid this type of trap is to ensure you have quality data management and hygiene practices in place to remove hard bounces and ensure all recipients on your mailing list receive at least one email from you every couple of months (at the very least).
Pristine traps are mailboxes that will never sign up to receive any kind of marketing material. They are set up from scratch to be spam trap addresses and should be taken the most seriously because if you’re sending to email addresses that never legitimately signed up, you cannot get their consent. And if you don’t have permission to email someone, you run the risk of not only hitting spam traps but also racking up a lot of spam complaints, both of which can damage your deliverability.
The two main ways pristine traps show up on your mailing list are through the use of purchased (or scraped) data, or if you have unsecured sign up forms. The best way to avoid pristine traps is to collect an opt-in from all recipients before emailing them, and to validate their signup by using a confirmed opt-in (COI) process. Also ensure all submission forms are locked down with a CAPTCHA, or one of the alternate forms of protection available to prevent bot signups.
Tamara likes to differentiate between “indicator” traps and “problem” traps since one type can negatively impact deliverability, whereas the other can be of great help in detecting issues, potentially allowing you to avoid deliverability issues altogether.
Indicator traps are run by ESPs or deliverability vendors (like Kickbox!) and they do not impact deliverability. Their purpose is to help you identify problematic practices and improve them before they damage sender reputation. For example, our Deliverability Monitoring Suite tells you how many traps you’re hitting within our network, as well what sender addresses, domains, IPs and subject lines were used to hit the traps, so you can trace those issues back to the source and plug up the hole where spam traps are entering.
On the other hand, “problem traps” are those owned and managed by MBPs or by anti-abuse providers such as Spamhaus and SpamCop. Hitting these traps can result in blocklistings (also referred to as “blacklistings”), as well as your mail being throttled, sent to the spam folder or outright rejected by MBPs.
In general, the best way to avoid hitting spam traps is to have a quality opt-in process and a close eye on list hygiene. Be wary of any vendor who claims they can identify and/or remove all of the spam traps on your list. If they provide you with a list of spam traps, resist the temptation to simply remove those traps and go back to business as usual. Instead, use that data to uncover the source of your issue!
FAQs about Deliverability Issue Resolution
Since there are a myriad of directions you can go with resolving issues, we’ve listed some guidelines based on the challenges our customers face most often.
How long does it take to resolve an issue, and what’s the most effective way to handle it quickly?
My typical (albeit frustrating to hear) answer is usually “it depends.” Perhaps you’ll like how Tamara puts it better: “How long is a piece of string?”
Each deliverability issue is unique, so the measures you need to put in place and the length of time it will take to resolve the issue can vary greatly from a couple of hours to days or even months.
It’s rare to come across a delivery or deliverability issue that can’t be solved with enough patience and persistence. The question is, how much are you willing to improve your email practices and workflows, and how quickly can you do it?
If you aren’t 100% confident about the cause of your issue, even after answering the questions above, an important first step is to eliminate all the most obvious best practice issues first. MBPs will note these positive changes within your technical configuration, sending statistics and/or recipient engagement, resulting in an improved sender reputation. Even if it doesn’t solve your issue right away, aligning your email strategy with industry best practices will almost certainly benefit your email program in the long run.
If you do know what’s causing your issue, take action as quickly as possible! Every email you send with improper authentication, poor statistics or a lot of negative reactions from recipients will exacerbate your issue, making it take that much longer to resolve.
When should I reach out to a Postmaster for help or to request mitigation?
It’s important to understand that Postmasters help those who help themselves. You should only consider reaching out when you are completely confident that you have resolved all underlying issues or if your investigation has come up empty and you are in need of additional information to understand what’s gone wrong.
If you’ve reached the point where you feel you’re abiding by all of the MBPs requirements and are deserving of mitigation to solve your issue, here are a few suggestions:
- Provide details. Always include the sending IPs and domain you send from, as well as a short summary with details pertinent to your case: the type of mail (i.e., transactional, marketing) and content you send (i.e., newsletters, welcome emails), what you believe triggered the issue, when it started, and any meaningful changes the sender has made to warrant them removing the block or otherwise intervening to mitigate the issue. If your email bounced, provide the bounce message, including the alphanumeric codes. Those don’t mean anything to you, but they matter a lot to MBPs when reviewing your request.
- Be clear and concise. While some of the details above are necessary, and others allow the Postmaster to help you more quickly, keep it as short and sweet as you can. Remove details that don’t clearly support your case. And always end with what action, specifically, you want the Postmaster to take.
- Be kind. Remember that, in most cases, you are dealing with an actual human whose job is to help you. Being nice might not magically solve your issue, but it will make that experience more pleasant for both of you, and who knows: it might just inspire the person you’re dealing with to help you out or share some additional information about how you can help yourself out.
- Have persistence! It can sometimes take multiple interactions with Support to identify the cause of your issue and have the Postmaster agree to mitigate it. Stay patient and repeat the important details of your request (such as sending IP and domain) with each follow-up, so they never get lost.
- Hold yourself accountable. If a Postmaster comes back with a list of things you should be doing, make sure you’re following all of those recommendations, not just the ones that seem easiest to tackle or most important to you. If you feel one of them doesn’t apply to you for some reason, check back with the Postmaster to further explain your situation and clarify the recommendation.
Can I solve my deliverability issue by sending from a different IP address or ESP?
The short answer: “No.”
We’d love to tell you that outrunning your deliverability issues was this easy. Unfortunately, it’s not usually the case. MBPs have become more sophisticated over the past several years, and domain reputation continues to play a bigger role in determining a sender’s reputation. And since domain reputation is tied to your sending domain (which is also usually tied to your company’s website), it can follow you, even if you switch IPs or ESPs.
Check out our recent post on Common Email Deliverability Myths to learn more about when changing IPs or ESPs might be appropriate for your business.
Solving deliverability issues is not always an easy process. Asking the right questions and taking the right steps to improve your email program allows you to resolve your deliverability issues more quickly and may even help prevent some of them from happening in the first place!
Stay tuned for more awesome content
Email Deliverability Unfiltered is a monthly video series. Now, you have even more ways to listen. Email Deliverability Unfiltered the podcast is now streaming on all of your favorite listening platforms: Spotify, Apple Podcasts, Stitcher, and Anchor.
Check out our previous episode, Common Email Deliverability Myths, as we dispel myths circling the email community and our interactions with customers, from general email marketing myths and email content to myths about data collection and email verification.
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