[SOLVED] Configuration issue: Mail for [host]:25 loops back to myself


New Member
Apr 29, 2023
I am struggling for a couple of hours with my second PMG installation and I am encountering an error while testing inbound mail.
Here is what I am getting in return to the sender's mailbox:
and here is what I am getting in the Tracking Center:

Here is my PMG relay configuration:
My Options page looks like this:

I have another installation of PMG (v7) for another mail server, with almost identical setup and it works great, but not this one.

What do I do wrong? What does the "loops back to myself" error mean?
Any hint would be greatly appreciated as I have run out of ideas :(

I fixed it. It turned out that the target relay server (Lotus Domino based) presented itself in the HELO message with the same name as Proxmox MG which apparently confused PMG and made it reject the messages.


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