I have a problem with double posting error messages which my list subscribers are receiving every time the post to the list. I have searched through the archives and found several references to this problem however I have not been able to identify which subscriber is mirroring messages back to my list since there is no identifiable domain in the email headers. I suspect that it is the IP address 80.253.119.74  which is the culprit and have traced this to ns2.softflare.net which is a company providing web hosting services however no subscribers on my list use this domain. Does anyone have any ideas on how I might resolve this problem? I have included the error message and headers below.
 
Kind Regards
Ingrid Walker
Email: [log in to unmask]
 
Your message is  being returned to you unprocessed because  it appears to have
already been distributed  to the PTNC 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.
 
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Subject: [PTNC] Test message 06/01 (2) - Please ignore 
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