[ILUG] mail duplicates

[Kevin Philp]

On a slightly different note we have a client who bombs us with duplicate 
mails, is this an example of a "moron with exchange" that you talk about? We 
have just started doing a lot of business with this guy and I can sense a 
mountain of complaints coming my way! Below is the bit of the header that 
comes from his server and can be found in all the duplicates... it sounds 
like the same POP and multidrop problem we discussed earlier. Before I start 
complaining to him is there anything I can do at my end?


Received: from *************.local ([10.19.0.2]) by **************.local with 
Microsoft SMTPSVC(5.0.2195.5329);
         Fri, 19 Mar 2004 13:16:29 +0000
Received: by ******************.local (Microsoft Connector for POP3 Mailboxes 
5.00.2195) with SMTP (Global POP3 Download)
         id MSG03192004-131615-5638.MMD@********.com; Fri, 19 Mar 2004 
13:16:15 -0000




Kevin Philp wrote:
> We have one user who works off site and they have a virtual pop box with
> the name anne at cybercolloids.net. The problem is that the ISP, correctly,
> feeds annes mail to the VPOP box and the rest to out multidrop box. However
> if the mail is sent to fred and copied to anne it ends up in both boxes and
> our mail server then sends anne another copy because it doesn't know she
> has already got a copy from the vpop box. Is there some way I can stop our
> server duplicating mail for anne.

This is why splitting up email collected via POP based on headers rather
than envelope (which is of course unavailable) sucks. Especially when
the mail server is misconfigured to attempt delivery for _every_ email
address it finds in the headers. (Although I've only ever seen this
with morons running Exchange.)

As Rick would say, don't do this. Use the correct protocol for the
job: SMTP.