Why the from and the sender are not the same thing?

[Julian Field]

In addition to my other comments, I refer you to my posting entitled "Re: 
Whitelist Problem -- explanation of To: versus recipient" on the mailing 
list on 13/August/2002.
This explains the difference between the envelope and the headers.

At 15:35 20/08/2002, you wrote:
>Hi,
>
>I received some messages like this:
>
>
> > The following e-mail messages were found to have viruses in them:
> >
> >    Sender: <Webmaster at cegeptr.qc.ca >
> > Recipient: <infoprog at cegeptr.qc.ca>
> >   Subject: Scrolling
> > MessageID: g7KE78FF002666
> >    Report: /g7KE78FF002666/Yzdsr.scr        Found the W32/Klez.h at MM virus
>!!!
> > Windows Screensavers often hide viruses in email in Yzdsr.scr
> >
> > Full headers are:
> >  Return-Path: <g>
> >  Received: from Jcdyf (hurricane-ppp29.sorel.cognicase.net [64.254.11.35])
> >   by courrier.cegeptr.qc.ca (8.12.5/8.12.5) with SMTP id g7KE78FF002666
> >   for <infoprog at cegeptr.qc.ca>; Tue, 20 Aug 2002 10:07:09 -0400
> >  Date: Tue, 20 Aug 2002 10:07:08 -0400
> >  Message-Id: <200208201407.g7KE78FF002666 at courrier.cegeptr.qc.ca>
> >  From: webmaster <webmaster at johnabbott.qc.ca>
> >  To: infoprog at cegeptr.qc.ca
> >  Subject: Scrolling
> >  MIME-Version: 1.0
> >  Content-Type: multipart/alternative;
> >   boundary=BBowx3aO8i4OBHwS930B5Us0800A2M03
> >
> > --
> > MailScanner
> > Email Virus Scanner
>
>I don't understand why the sender is webmaster at my.domain and in the header
>is webmaster at johnabbott.qc.ca
>
>The user's auto-response goes to webmaster at cegeptr.qc.ca
>
>I'm using mailsanner 3.20-7 with no spam detection and Mcafee
>
>Somenone knows what is my problem?
>Thanks!
>
>Jonathan

--
Julian Field                Teaching Systems Manager
jkf at ecs.soton.ac.uk         Dept. of Electronics & Computer Science
Tel. 023 8059 2817          University of Southampton
                             Southampton SO17 1BJ