Yesterday we launched an email around 2 pm PST to a very small segment of lead DB.
Around 8:00 pm PST we received around 200 auto-replies in outlook inbox. I tried to search for the domain or email in my DB but I could not find anything related to the email below in my DB. All the auto-replies has the same domain- ".itscom.net'.
Below are the details of errors-
Original Message Details
Is this Marketo delivery issue or some Microsoft outlook issue. I searched the web but could not find any resolution to that. I am not a domain or email deliverability expert so looking for suggestions to resolve the issue.
While this could be due to buggy filtering at O365 -- see this thread from today -- you need to be precise about the domain(s) that's generating the error.
s00.itscom.net isn't the same as itscom.net. They have different MX records and so should be considered completely separate, as if they were apples.com and oranges.com.
In your database, is the recipient @itscom.net or @ the subdomain? Is it possible that you did a bulk load of people at a certain subdomain, and they recently discontinued use of that domain, merging the mailboxes into the parent domain? (This can happen when people upgrade their systems to support more users on the same server.)
How can I stop sending to same subdomain or domain?
I want to add the domain or the email in my exclusion list but I am not able to find the name in the DB.
Can you please suggest any resolution to this issue. Does this kind of things impacts deliverability of the emails in futire?
I have to do another batch of the email but I am not sure if I should take some steps before the execution.
I am not able to find the name in the DB.
Then the domain is probably being aliased somewhere within O365. This can make things very hard to track.
You don't see just the mailbox names (museedagri in this example) in your DB?
I did not find this or any other name with same domain in the DB.
I'm asking if you searched by the mailbox (not the domain, the left-hand-side only).
Yes I searched for names "mailbox names (museedagri in this example)" but I could not find any result in Marketo and Salesforce with this name.
Without more information in the notification (sometimes, a failure notice contains a copy or partial copy of the original message) there isn't enough to go on to track it down. Of course if you whittled down the list you could eventually find the original recipients by trial and error.
My hunch (though unproven) is you have 200 people at one specific subdomain, or perhaps set of subdomains, and that has become obsolete (the mailboxes may all have been moved to a new domain, but you didn't hear about it). Now, mail goes to a set of catchall mailboxes, but those catchall mailboxes are broken.
With more visibility into your system I'm sure I could figure it out, but from here it remains opaque.