Backscatter & challenge response {Scanned by Allteks Mailsafe}

[Paul Houselander (SME)]

If your domains outbound e-mail goes via servers you control/have ms running
on them take a look in MailScanner.conf at the Watermarking section.

I run ms for many domains not all send their outbound via me so I use
rulesets to only add a watermark for certain domains and only check them for
certain domains, has worked a treat, only problem is that some read receipts
and out of office replies get incorrectly flagged, small price to pay to
block all the rubbish I think!

> 
> Hi there,
> 
> Sorry for jumping in on this - but wondered how you went about
> watermarking? I use Sendmail / MS
> 
> Regards
> 
> > Hi
> >
> > In common with lots of people I've seen a massive increase in the
> amount
> > of
> > backscatter my domains are getting. I implemented watermarking which
> has
> > helped a great deal.
> >
> > What I'm getting complaints about now are the mails coming in from
> > annoying
> > challenge response systems, the mails don't come from postmaster, <>
> > etc...
> > so the watermark does not get looked at.
> >
> > Just wondered if anyone had any bright ideals as to how to combat it?
> >
> > I've been looking at a selection I've been sent through this morning
> and
> > there doesn't seem to be anything consistent about them and there not
> > hitting many spamassasin rules.
> >
> > Cheers
> >
> > Paul
>