On our mailing application we are sending emails with the following header:
FROM: marketing@customer.com
TO: subscriber1@domain1.example
Return-PATH: bouncemgmt@ourcompany.example
The problem that we are facing is that some email servers will bounce back a message immediately and use the from or reverse path (marketing@customer.example) instead to our bounce mgmt server. We want to know if we modify in the header the reply-to to be the same as the return-path if we will be able to catch all bounces.
Any other ideas are welcome?
We are using the following documents as references: VERP RFC Bounce Messages
SMTP Log Parsing to get Bounces
EDIT 1: A few more bits of information to see if we can get this resolve.
We want to know at what point the email server relaying the message will choose to use the reply-to versus the return-path. We have notice that when the first SMTP server relaying the message gets rejected it sends it to the reply-to, but when it happens after one hop it sends it to the return-path.