[Pkg-exim4-users] How to get around "Must issue a?STARTTLS?command first"

[Andreas Metzler]

Norbert Preining <preining at logic.at> wrote:
[...]
> As I said, I am trying to deliver emails to the smtp server of my
> university as it is my ISP.

> I have set in
>        /etc/exim4/conf.d/main/000_localmacros

> DCsmarthost=smtp.host.foo.bar::587

> (actually I have a lookup into /etc/smarthost with
> ${lookup{*}lsearch{/etc/smarthost}{$value:}{}}
> plus a fall back)

> but any time exim tries to send an email out via that smtp I get an 
> error message telling me

> ...
>  590885 at bugs.debian.org
>    SMTP error from remote mail server after MAIL FROM:<preining at logic.at>
> SIZE=2963:
>    host XXXXXXXXXX [NN.NN.NN.NN]: 530 Must issue a STARTTLS command
> first
[...]

Hello,
Since exim will automatically use STARTTLS if available (unless
disabled with hosts_avoid_tls or hosts_avoid_esmtp) I suspect there is
some "smart" router/firewall in between you and the server exim is
trying to deliver to. Said router is filtering/rewriting the SMTP
dialogue, disabling SMTP. Cisco router with the "smtp fixup" setting
enabled are notorious for this behavior.
cu andreas