[Info-vax] VMS MAIL, TCPIP, SET FORWARD/USER

[Simon Clubley]

On 2011-11-29, Phillip Helbig---undress to reply <helbig at astro.multiCLOTHESvax.de> wrote:
> To deal with some non-existent addresses which receive more than a bit 
> of spam, I did
>
>    MAIL> SET FORWARD/USER=<nonexistent address> NL at multivax.de
>
> where NL is an empty file with type .DIS in TCPIP$SMTP_COMMON.  This 
> works as expected (i.e. it is a black hole).  However, today I got an 
> email to this address in the mailbox of a real user.  How could this be?
> Could it be that the real user was on Bcc: and the non-existent user 
> shows up in To:?
>

Don't confuse the message envelope (used by SMTP for delivery instructions)
with the message headers (used by email clients).

The information in the message header itself is not used by SMTP for
delivery and although it should be the same as the RCPT TO: command
in the message envelope, it doesn't have to be.

BTW, you don't say what SMTP server you are using, but the way I have
the SMTP server in TCP/IP Services configured (assuming the mailbox
lives on the same machine as the SMTP server) is to check for a valid
email address and reject the email before it's delivered if the
destination address does not exist.

Simon.

-- 
Simon Clubley, clubley at remove_me.eisner.decus.org-Earth.UFP
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