Overview
Every email sent & received has message headers,
which includes information such as where the message originated from
where it is sent to.
Viewing headers
Outlook: open the email, then select File, Properties, Internet Headers
Outlook Express: open the email, then select File, Properties, Detail
Thunderbird: open the email, then select View, Headers All
Webmail: open the email, then select View Full Headers
Forwarding the Headers
Copy & Paste the headers into the email when forwarding the message to us for analysis