Re: Invalid RCPT TO: list

RCPT TO: <user1@xxxxxxxxxxxx>, <user2@xxxxxxxxxxxx>,
<user3@xxxxxxxxxxxx>

No, it *should* be:

RCPT TO: <user1@xxxxxxxxxxxx>

RCPT TO: <user2@xxxxxxxxxxxx>

RCPT TO: <user3@xxxxxxxxxxxx>

As you can see, the recipients are broken down into seperate user and
RCPT TO: addresses.

....as is absolutely standard!

a) If the application is sending out RCPT TO: <user1@xxxxxxxxxxxx,
user2@xxxxxxxxxxxx, user3@xxxxxxxxxxxx>, why is IIS sending out (or
looks to me like it is) RCPT TO: user1@xxxxxxxxxxxx, RCPT TO:
user2@xxxxxxxxxxxx etc.

The real question is what makes you believe that said mails are not
being delivered to the final recipient (which was your original
premise). What happens to those outbound connections? What does the
log show as the reason for final delivery failure?

b) If IIS is sending RCPT TO: list as three users, what recipient list
does the MTA at Server3 see?

It sees a list (usually an array) with three users.

But a "recipient list" is a logical concept that may be implemented in
any fashion by an MTA. It might well just be a text file with an
arbitrary number of lines. The important thing is the recipient list
be persistently linked with the original message headers/body, while
failed/successful delivery to each recipient is separately tracked.

I would have thought the RCPT TO: list would stay the same as it
progressed through each MTA?

Not necessarily -- an MTA may be forgiving and allow for non-standard
envelope information on the way in, but "massage" the envelope into
standard form on the way out.

Also, if an MTA knows a given RCPT is an alias for a "more true"
recipient or set of recipients, it is perfectly free to transform
and/or expand the recipient list before making the outbound
connection.

--Sandy


------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
------------------------------------
.

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