From: DeskNow Knowledge Base
http://www.desknow.com/kb/

How can I get the source of an email message ( .eml format)
http://www.desknow.com/kb/idx/4/179/article/

Email messages are transferred between computers in a standard format, defined by the MIME standard.

This is detailed in the RFC 822 internet document (and refined in many others).

Messages in this format are normal files, containing only text characters. The file contains all the message headers, the body (text) of the message, and encoded attachments.

A common extension for files in thes format is .eml , and it is the one used by DeskNow. Internally, DeskNow stores all email messages in this format, in the /desknowdata/usermail folder

Exporting a message in .eml format

To export a message in this format from the web interface, simply open the message, then click on the blue 'i' icon. This will open up a windows showing all the message headers. Click on the 'Download' button in this window to download the entire message as .eml file.

Befoire emailing .eml files, it is recommended compressing them to zip or tar.gz