[Mimedefang] resending mails from quarantine, modify Message-ID or use Resent-Headers?

[Peter Bonivart]

On Tue, Jan 3, 2017 at 7:19 PM, Marcus Schopen <lists at localguru.de> wrote:
> Hi,
>
> I'm playing around with resending quarantined emails, if the user wants
> them to be delivered and check locally. I set Resent-Headers in those
> resent messages, so that cyrus delivers and doesn't drop them as
> duplicates. Some users users pop their mailboxes with exchange or
> popcon. Any experiences out there, if those messages get dropped by pop
> clients because of the same Message-ID or should I better change the
> original Message-ID header to something like X-Orig-Message-ID and set a
> new Message-ID header?

Exchange has had a duplicate message protection looking at the message
ID for a long time. I generate a new message ID to avoid that.