> I am unable to figure out why because Princeton's system makes it impossible
> for me to figure out who the posting was intended for.
 
Maybe I'm being dense, but I don't see the problem.  Isn't it obvious
that the posting in this case was intended for the user mentioned in
the SMTP transaction?  I.e.,  <[log in to unmask]>.  Isn't it
just a matter of removing that user from the subscriber list?
                                            John
> ----------------------------Original message----------------------------
> The enclosed  mail file, found in  the HELP-NET reader and  shown under the
> spoolid 7541...
 
> Date: Tue, 26 Feb 91 09:25:19 EST
> From: <[log in to unmask]>
> To: <[log in to unmask]>
> Subject: Undeliverable Mail
>
> pucc.PRINCETON.EDU unable to deliver following mail to recipient(s):
>     <[log in to unmask]>
> pucc.PRINCETON.EDU received negative reply:
> 550 (USER) Unknown user name in "[log in to unmask]"
>
>            ** Text of Mail follows **
...