Identifying reasons of the Soft Bounces

[raiashutosh]

Hi  Guys,

We are facing a soft bounce issue in our recent email sends. Our deliverability has dropped from 98% to 91% in the last two weeks. I am yet to find a cause of this issue, I can rule out the below reasons:
Covid situation - As it was fine till the last 2-3 weeks
Audience Persona - We haven't change the criteria of the target audience
Audience Volume - There isn't a sudden change in the sending volume.

I also tried creating the Smart campaign  with the filter: Email bounce soft, created a new view and added the fields - Email Invalid Cause, Email Suspended Cause, but they were all were empty.
I stumbled upon an article that explains all the reasons corresponding to all the bounce codes >> https://nation.marketo.com/t5/product-discussions/summary-bounce-codes-reasons/td-p/131427

If I can find a way to find at least the bounce code corresponding to the individual lead then it will be easy to identify the cause of the sudden decrease in deliverability.

However, we realized that the deliverability has dropped since I started using tokens in our email header, this is just an observation. I am planning to send an email without the tokens to actually prove my hypothesis.

Anyways, if you guys have any ideas or you faced a similar issue please share the solution.

Thanks!
Ashutosh Rai

[Vinay_Kumar]

Hi @raiashutosh,

There could be many reasons for a soft bounce. Here are a few:

1. undefined mailbox status
2. Mailbox disabled, not accepting messages
3. Mailbox full
4. Network congestion
5. Too many recipients
6. Mailbox is inactive
7. The recipient email server has been sent too many emails during a period of time.
8. Email message blocked due to content.
9. Email message does not meet the recipient server’s policies.
10. The domain name does not exist.

To find out the leads and bounce details you can try the below-shared combination: 

Hope this will help you identify the reason for the soft bounces.

Thanks

[raiashutosh]

Hi @Vinay_Kumar 

Thanks for helping with the reasons, I am looking for these reasons associated with the individual leads so that I can understand the most common reason.

The second filter in your example seems to be a custom filter, can you share if it can give the reasons of soft bounce or atleast the bounce code.


Thanks!
Ashutosh

[Balkar_Singh]

Alternative way to narrow down on reasons would be adding the constraint of Category in the filter for the Email Bounced, and creating 3 such smartlists. However, where did you get the codes from if not from the Email Invalid Cause Field?

[raiashutosh]

@Balkar_Singh 
I got this from an article on Marketo resources, these codes are default system codes.
The email invalid cause field only gives the reasons for hard bounces.

I am looking to find the reason for the soft bounce so that I can take some action to avoid this in the future.
The alternative way you suggested seems interesting can you please explain, i have already used the email bounced soft filter to get all the soft bounce emails.

Thanks!
Ashutosh Rai

[raiashutosh]

I've further investigated this issue, the sudden increase in the soft bounce has occurred post 9th August.
Also, the majority of the soft bounce is of Category 4.

Another finding is that almost 50% of the soft bounce category 4 ids are yahoo.com.
Is there been any change in the algorithm of Yahoo recently.

Thanks!
Ashutosh Rai

[Vinay_Kumar]

@raiashutosh, Please check your recent email send to identify whether you are facing soft bounce for all the Yahoo domain email addresses, or do you have some of the yahoo domain email addresses that have received your email?

Yahoo is regularly disabling and canceling all accounts that have been inactive for more than a year. A disabled or frozen account could also be a reason for the email bounce.

[raiashutosh]

Hi @Vinay_Kumar 

Thanks for your suggestion, yes around 505 of them were Yahoo. We're still investigating, I am looking into details to find if all those soft bounces were old leads and at which stage they are, in our journey.

Strangely, the soft bounce numbers have gone back to normal in our last emails.
We were using tokens in the header of our email(banner img, banner links), just to check, this time replaced the tokens with content and the soft bounce numbers are back to normal.

We were planning to suspend those soft bounces, but the email got delivered to them in our recent send.

I'll update here as soon as we come to a conclusion.

Thanks!
Ashutosh Rai

[Vinay_Kumar]

@raiashutosh, Thanks for sharing the updates. 

Would love to see the outcomes.