Nurture Stats Overview

[Paulina]

Hi,

I'm looking over the an emails (we have A/B Subject line test) that are part of the MAL>MEL nurture. Here are the stats of the seconf email that are concerning:

% Delivered 80.4% & 80.0%

Hard Bounced 596 & 634

Soft Bounced 3986 & 4039

Any ideas or suggestions what went wrong?

[Darshil_Shah1]

Could you please be more specific on what exactly is concerning here? Is it the high number of bounces or people having delivered and bounced activities for the same email send activity? It'd be helpful if you could provide more context here. Just adding responses on the couple of possible cases below, in case any/both of them apply to you.

For the former, do you see the reason/Details in the activity log of the bounced people? However, that may not be 100% accurate as Sandy mentioned in a post earlier (recipient servers are not bound to return the accurate reason for rejecting emails). Nevertheless, seeing what reason was logged in Marketo for the rejection of emails could help give us some hints.

For the latter, an email may simultaneously have a Delivered and Bounced status. This happens in cases when it gets Delivered at the first hop (immediate connection to the recipient's MX) and then bounces at a second hop. By the second hop, it's too late to send an actual SMTP-level rejection, you can't undo the Delivered.

[Paulina]

Hi Darshil, thank you for the reply. Our deliverability of emails both nurture and promotional are always above 90 %. This is the first time I'm seeing lower deliverability and got consorned. 

I've looked at couple of people who got bounced and here are some of the details of the reason:

• 550 [internal] [oob] The message failed for unspecified reasons.
• 554 5.4.7 [internal] (last transfail: 421 4.4.0 [internal] no mail servers for this domain could be reached at this time)
• 550 [internal] [oob] The message was blocked by the receiver.

[Darshil_Shah1]

Thank you for providing details, @Paulina! Did you add a lot of new people to this nurture recently or change your content? I've tried outlining the meaning and probable cause of the bounce codes/reasons shared by you. But again, as I said earlier, all the bounce reasons you see in Marketo might not be 100% accurate due to the discretion of receiving mail servers.

550 [internal] [oob] The message failed for unspecified reasons.

This bounce message indicates that the email delivery was unsuccessful, and the reason for the failure was not specified in the response. The "internal" and "oob" tags usually refer to internal error codes or flags used by the mail server to categorize different types of errors. In this case, the exact cause of the failure was not provided

554 5.4.7 [internal] (last transfail: 421 4.4.0 [internal] no mail servers for this domain could be reached at this time)

This bounce message suggests that the message encountered a 554 5.4.7 error code. The "5.4.7" part of the code generally indicates a problem with the email delivery, and the "554" code specifically refers to a "Transaction failed" error. The "internal" tag might again indicate an internal error code used by the mail server.

The additional information in the parentheses gives more context about the issue. It states that the last transmission attempt (transfail) failed with a 421 4.4.0 error. The "4.4.0" code often points to a temporary failure or a transient issue. The specific error message, "no mail servers for this domain could be reached at this time," suggests that the recipient's mail servers were not reachable during the delivery attempt. Such errors are usually temporary.

550 [internal] [oob] The message was blocked by the receiver.

In this case, the recipient's mail server actively blocked the delivery of the message. The "internal" and "oob" tags might again refer to internal error codes or flags used by the receiving mail server.

There could be various reasons for a message to be blocked by the receiver. Some common reasons include:

• The recipient's email server has a strict spam filtering policy, and the message was flagged as spam.
• The sender's domain or IP address is on a blacklist maintained by the recipient's mail server, indicating a history of suspicious or spammy activities.
• The recipient's mailbox may be full, and the server may reject incoming messages until space is cleared.
• The content of the email triggered certain filtering rules set up by the recipient.

Based on the error(s) you've encountered more and the reasons above, I'd recommend you have a look and try finding a probable explanation (e.g., content/audience was changed, etc.) on why your delivery rate decreased, and bounce rate increased.

[Paulina]

Thank you for this explanation, Darshil. 

[Chris_Willis1]

Hard bounces are fairly straightforward because you will get an error code that indicates why the email bounced. 

Soft bounces are more difficult, but they are a leading indicator of issues that you should look at via Deliverability.  A "soft bounce" is a return when Marketo attempts over and over to deliver an email and it is ultimately unsuccessful.  

You may or may not get a return code, which I understand is frustrating.  However, the percentage of soft bounces can be an indicator of an inbox deliverability issue in your pod that you should start paying attention to. 

A few things to look at with as high of a soft bounce % as you are seeing:

1.  What are the percentage of complaints you are seeing?  This can be seen in a Revenue Explorer report. 

2.  What % of your emails are going to spam or to promotion folders?  You'll need the deliverability tools to see this data (as it relies on seedlist tests).  

[Paulina]

Hi Chris, thank you for the reply. We don't have Revenue Explorer functionality. As far as I know, we don't have any deliverability tools.