This page explains how to backup your email.
Before you decide which option to choose to backup your email, you need to evaluate the importance or operational need for the information. This is a practice called records management.
For more information about records management, please see http://en.wikipedia.org/wiki/Records_management.
For Information about Western University's Records and Archives Policy, please see http://www.uwo.ca/univsec/pdf/policies_procedures/section1/mapp130.pdf
Depending on the percentage of messages which meet your requirement you can consider the various options listed below:
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