Something else to consider....Just last month I ran into this same
problem. The lists are internal to our company. Found out there were new
mail filters installed and because the password was indicated as 'XXXXXX',
the filters thought it was offensive mail. But yet the "Your message has
remained unconfirmed for 48 hrs" message would still come through fine.
The mail folks created an exception, but last week I subscribed to another
peach.ease.lsoft mail list and the same thing happened. So their exception
in the mail filter was very specific to my internal lists.

S. D. Dobbs
Hercules Incorporated
[log in to unmask]
http://www.herc.com/





Roger Fajman <[log in to unmask]>
Sent by: "LISTSERV list owners' forum" <[log in to unmask]>
03/05/2004 11:59 PM
Please respond to "LISTSERV list owners' forum"


        To:     [log in to unmask]
        cc:
        Subject:        Re: List mail, no LISTSERV job outputs


At 09:41 PM 3/5/2004, you wrote:
>Lately we have been having an increasing problem with people not being
able
>to subscribe because they never receive the confimation messages, so they
>can't confirm.  Once we manually ADD them they receive the list mail just
>fine, but they still don't receive any job outputs from LISTSERV,
>regardless of what it is they do, or try to do.

When an SMTP server passes a message to another server, it uses a command
language that, among other things, says where error messages should be
sent
(MAIL FROM) and to what addresses the message should be delivered (RCPT
TO).  Here's what a typical MAIL FROM command looks like:

         MAIL FROM:<[log in to unmask]>

If the message cannot to delivered to one or more of the RCPT TO
addresses,
an error message will be sent to this address.  The message is still
delivered to the other recipients.  When LISTSERV replies to a command, it
uses a special null form of MAIL FROM:

         MAIL FROM:<>

This means that delivery error messages for any of the recipients will be
discarded.  LISTSERV does this because it has nothing reasonable to do
with
the error messages.

Some ISPs are blocking messages with the null MAIL FROM in the mistaken
idea that such messages are spam.  In fact, all delivery error messages
are
sent with a null MAIL FROM, so there are many more messages involved than
just LISTSERV's.

About all anyone can do is to contact the sender's ISP and hope for the
best.

Roger Fajman