Hi. I was wondering if perhaps your list is being "broadcast" via some
exploder list...I may not be using the right terms, but this is how it was
explained to me.  If someone has taken your list and is broadcasting it to
another bunch of people, and if one of *them* is in error, the errors come
back to you...and you can't find them.
 
I might try looking for something on my list that looks like a suspicious
provider..like sometimes people join my list with the email id
 
     LACTNETer@xxxx.com....
 
If the name of your list is in the email id of the subscriber, that may
indicate that the address is the gateway to the  exploder list...
 
I hope this is clear. I am not explaining this properly, I fear, but perhaps
someone here knows more.
 
Kathleen
 
Kathleen B. Bruce, BSN, IBCLC co-owner Lactnet,Corgi-L,TLC, Indep. Consultant
http://together.net/~kbruce/kbbhome.html
LACTNET Archives http://library.ummed.edu/lsv/archives/lactnet.html