Troubleshooting delivery problems


Everyone has their own way of troubleshooting problems. I thought I would list out the steps I take when I’m trying to troubleshoot them.

image of a head with gears and ideas floating around it
  • Clarify the problem. As a consultant, folks come to me asking me to help them solve their delivery problems. My first step is to get them to clarify what symptoms they’re seeing. Something happened to make them contact me, and that’s where we start. Questions at this stage include:
    • Is mail going to bulk?
    • Is mail being rejected?
    • Where is mail rejected?
    • Are open rates steady?
    • What mail is affected?
  • Once you have the answers to the question, you have your problems statement. This is a one or two sentence summary that identifies the full issue. This is a step a lot of folks avoid doing, but a good problem statement drives the troubleshooting. Example problem statements:
    • Marketing email from our ESP goes to bulk at Gmail.
    • CRM email is seeing high numbers of temp failures at Yahoo.
    • Our domain is blocked by Filter provider.
  • Identify what are likely causes of the problem. Filters are pretty specific, so you want to change things that will actually make the filters do something different. Not just apply random best practices you’ve found on a website or blog (even this one). Common techniques, like sending to engaged users or removing bounced addresses don’t work everywhere, so you may end up weeks down the line with no improvement to show for it.
    • “Improving engagement” only works if the problem is bulk foldering at the three big mailbox providers. It does nothing anywhere else.
    • “List hygiene” only works if the problem is your list isn’t bounce handled (which is never, if you’re using a real ESP).
  • Implement specific changes to address the reason for the delivery problems. What was the problem and how do you back it out? “
    • Our sales dude decided to harvest addresses of a social networking site and add them to our newsletter list. We purged all those addresses (or all the addresses that clicked on a link that wasn’t unsubscribe) from our list.
    • There was a flaw in our data handling process and we reactivated addresses that had bounced off in the past We fixed the flaw and have removed the previously bounced addresses.
    • We changed our frequency and ended up sending too much mail, causing recipients to report the mail as spam. We backed down to our old volume and are being more selective about who gets the new, higher volume mailings.
    • Some of our sales folks have not been abiding by company directives and are using addresses they’ve ‘saved’ from previous campaigns but that should be suppressed. We’ve implemented technical steps to prevent them sending mail to these addresses again.

All of these are actual solutions clients have implemented over the years. They’re all specific and required a clear understanding of mail processes and data flow. Once we identified the problems, the solutions fell out the end, really.

Too often, though, delivery folks don’t actually ask the right question and they don’t actually take the time to identify the problem. Instead, they “implement best practices” and try and make random changes hoping something will change. Some of the time it works, often the best practice change will randomly hit on the underlying cause of the problem. But when the random best practice changes don’t work, you absolutely need to step back and start from the beginning.

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  • Hi Laura,

    I have shared this with some of our colleagues, as this is a very good approach on how to get the senders to at least understand what they need help with and come to us with some more concrete questions than “help please”, so thank you for that.

    I would like to ask one question though, as one part of the post did not seem very clear to me. Here is the part:

    ““Improving engagement” only works if the problem is bulk foldering at the three big mailbox providers. It does nothing anywhere else.”

    By three big you mean Gmail, Microsoft and Verizon, I presume? However, Apple, on their own postmaster article, mentions that they do not provide Feedback Loops and that senders should “Periodically suppress inactive or disengaged subscribers from your mailing list.” in order to avoid deliverability problems. Deliverability problems with Apple usually means blocks, as far as my experience goes.

    So the question has 3 parts. Whether, by chance, a) you missed this information; b) you do not consider supression of disengaged subscribers as “improving engagement” and just use a different expression or c) your experience shows that this usually has no impact with Apple, even though they publish this information?

    Looking forward to your further insights and it’s always nice discussing with you!

    Best regards,

  • You said yourself: “Delivery problems at Apple usually mean blocks.” The situation you quoted was specifically ‘bulk foldering.’

    Apple’s advice is pretty standard and, overall, removing non-responsive addresses is generally a good idea.

    The type of engagement filters I was thinking about while writing the post are the ones where the MTA provider has direct insight into the inbox. In other words, engagement is about the user actions in the the email client feeding directly back into the filtering engine. This happens where the email client is tightly integrated into the MTA for the vast majority of users. While apple does have an email client, it is not tightly integrated into the iCloud MTA and user actions are not tracked and monitored. Furthermore, Apple uses a 3rd party filter (actually two, owned by the same company) to manage filtering for iCloud and addresses. This third party also does not have insight into the email client and does not monitor or track user actions in the mailbox.

    When I say “increase engagement” I specifically mean getting the folks receiving your mail to interact with it in more positive ways that tell the spam filters that the mail is wanted and should be delivered to the inbox. I don’t mean “make your open rates look better by decreasing the denominator.”

    Does that answer your question?

  • This is really an amazing flow. I’m gonna adopt the same. Thanks for sharing such a wonderful post.

  • question for you! what do you do next when the problem statement is as non-specific as “open rates are falling”? how would you go about getting from there to that next level of marketing email from our ESP goes to bulk?

  • The biggest issue I have heard from clients is list/lead management. The disconnect from sales, consulting (BD), and the marketing team is just bad. They generate and nurture leads, pass leads to inside sales: marketers receive no feedback for months.

    With delivery problems, most of the lists that they receive include a 20% no delivery rate because of old company contacts and other factors.

By laura

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