Re: sending a message failed

[Leo Butler]

On Thu, Mar 13 2025, gfp <gfp@posteo.at> wrote:

> Hi Gnus,
>
> I wanted to reply to a mail and I got an error message:
>
> Debugger entered--Lisp error: (error "Sending failed: 554 5.1.8
> <gfp@tuxedo.mail-host-ad...")
>   error("Sending failed: %s" "554 5.1.8
>   <gfp@tuxedo.mail-host-address-is-not-set...")

Hello,

The error message says `mail-host-address' is not set.
You can customize the variable thus:

M-x customize-variable mail-host-address RET

I don't think the value matters too much. You could set it to a string
that contains a non-routable FQDN, like "localhost.lan".

In Gnus, you can inspect the mail headers by typing t in the message
buffer. You can see what other Gnus users do by looking at the
Message-ID header: the text to the right of the @-sign is the
`mail-host-address' of that Gnus user.

HTH,
Leo