Metrics Mayhem: Why Your Emails Are Bouncing

Help! They won’t let me in!

If you’re like me, you may have had this thought run through your head when attempting to get into the latest trendy bar. Or, as an email marketer, maybe it is when you were reading through the latest SMTP logs and seeing a high number of bounces. You probably find yourself asking, “Why am I getting blocked at the gateway?”

There are two types of bounces messages an email campaign can encounter that would prevent you from making it past the gateway:

  • Soft bounce: A notice that the email message was sent to an active address but was turned away before being delivered to the intended recipient. Often the problem is due to a temporary issue (like a server outage or full mailbox) or volume (telling the sender to slow down). The email may be successfully delivered if sent again later.
  • Hard bounce: A notice that the email message did not go through to the intended recipient because of a permanent failure; for example, email to an invalid address (unknown user), or a rejection due to spam filters. Simply sending the email again later will not result in successful delivery. If the bounce is reputation-related and the sender adjusts practices to improve reputation, resending may get the email delivered.

Bounce messages are your guide to help you further understand the reasoning or root cause for being stopped at the gateway. So let’s dive into some email best practice and identify why you are receiving them!

Infrastructure and settings. Confirm the basics are completeinfrastructure, authentication, and communication settings at the mailbox providers. 

List acquisition. Check every point of acquisition. Ensure that every address is valid, and especially watch for typos that result from “fat-fingered” typing (e.g., “[email protected]”). Capture and immediately remove any email address that has misspelled or incomplete domain. As easy way to avoid these errors is to require your subscribers to enter their email twice for additional verification

Welcome/confirmation email. Once the data is acquired, send a welcome or confirmation message, immediately removing any hard bounces. A 2015 Return Path study reviews the importance and opportunity that the welcome message also offer in driving and predicting future subscriber engagement. 

Sending strategy and list hygiene. Once your subscribers are in your email program, make sure you are sending in alignment with the expectations you have set. Email subscribers no less than once per quarter to lessen the risk of sending to spam traps or unknown users.

Bounce processing. Review internal processes for how your program handles both hard and soft bouncesHard bounces should be removed from your list immediately. For soft bounce, set a policy for how many times you will retry the send, then suppress the address if you’re unsuccessful. Use the SMTP codes as an additional guide to help identify and address underlying issues.

There are a number of variables to consider when you are receiving a high number bounces messages. Don’t do this alone! Use resources at your fingertips like Return Path’s Ultimate Guide to Email Deliverability, follow best practices, and you might find yourself exactly where you wanted to be all alongthe Inbox.

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