On Thu, 06 Nov 2003 11:47:04 EST, Nelly Yusupova <[log in to unmask]>  said:
> We sent out a newsletter to our users yesterday and it went out 4 times!
> Does anyone know why this happened and how to fix it?

Get at least 2 of the notes, and start comparing headers (particularly
the Received: lines). You will likely find that the first few (at the
*bottom*, they get added newest-on-top) are identical, and at some point
they diverge.  That's where the problem lies.

The problem could be any number of places - you may even find that
the very first Received: is different.  This means that the PC or
whatever is creating the mail actually posted it several times.

One common cause for multiple postings is if one machine sends the
mail to the next hop on the path, the receiving machine does in fact
get the mail OK, but for whatever reason (timeout, network burp, whatever)
the sending machine never actually receives the "I got it" acknowledgement,
so it retries the mail later.