Hi Team,

We are using Proxmox Mail Gateway (PMG).

When emails bounce or fail to send, PMG sends a message from mailer-daemon@<hostname>.
The problem is that this email address is not allowed by our SPF/DMARC settings, so other servers sometimes reject it.

Is there a way to change the sender address for these bounce messages to use a different domain that passes SPF/DMARC?

We looked in the PMG web interface but couldn’t find where to change it.

Thank you!

Please share the logs of such a message, and it's rejection - this should help getting a clear picture of which part fails, and what needs to be adapted.

in general changing addresses used by the mail-system is not a good idea.