Thanks for the help. I think I located the culprit -- I set his email to NOMAIL and the problem went 
away.

----- Original Message ----- 
From: "Wayne T Smith" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Tuesday, September 26, 2006 12:53 PM
Subject: Re: Erroneous error msg from listserv


> I'll guess one of your subscribers, or their mail system, is bouncing your message back to the 
> list.  You may need the help of your Listserv site administrator to see if this is the case and 
> find the subscription causing the problem.
>
> cheers, wayne
>
> John Mack wrote, in part,  on 9/26/2006 12:11 PM:
>> Every time I submit a message to PHARMA-MKTING listserv (I am the moderator and owner), I get the 
>> following error message:
>>
>> Your message  is being returned to  you unprocessed because it  appears to have
>> already been  distributed to the  PHARMA-MKTING list.  That is, a  message with
>> identical text  (but possibly with different  mail headers) has been  posted to
>> the list  recently, either by  you or  by someone else.  If you have  reason to
>> resend this message to the list (for instance because you have been notified of
>> a hardware failure with loss of data),  please alter the text of the message in
>> some way and resend  it to the list. Note that altering  the "Subject:" line or
>> adding blank lines at  the top or bottom of the message  is not sufficient; you
>> should  instead add  a  sentence or  two  at  the top  explaining  why you  are
>> resending the  message, so that the  other subscribers understand why  they are
>> getting two copies of the same message.
>>
>> My message gets posted to the list OK. I do not send duplicate messages as far as I am aware. I 
>> also get this error message when I send from my hotmail account (which is a regular subscriber 
>> account). This leads me to believe that everyone who posts a message gets the same error, which 
>> can be confusing.
>>
>> Any ideas how I can stop this?
>