I noticed that the person posting to theses newsgroups, as shared by
Annelies, uses hotmail. I also use hotmail.com as an email service.
Accordingly, I know that hotmail has a "no tolerance" policy for spam as
well as other types of Internet abuse. They request copies of the
offending mail (including headers I suppose) to be sent to them directly
at mailto:[log in to unmask]   They will immediately terminate mail
service for the offenders.

This is generally true for most email service providers. One can always
try to alert a system administrator at the domain name following the @
sign in the email address. I am not particularly saavy about how one
might do this for systems other than hotmail, but many have web pages
where you could go to find a "contact us" link.

Katharine West, BSN, MPH
Sherman Oaks, CA