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With few exceptions, we do not recommend anyone use Outlook 2011 for Macintosh as their email client to access their MIT Exchange email and calendaring. Outlook 2011 lacks the external file features found in both Apple Mail for Mac OS and Outlook 2010 for Windows which would make recovery from a failure straightforward and easy. Instead, Outlook 2011 for Mac stores all emails and calendaring data in one massive proprietary database that cannot be recovered once the database becomes corrupted. What's worse the chances for data corruption and actual performance degradation increases with the size of the data base. It is therefore critical if you are one of the few exceptions using Outlook 2011 that you have at minimum a working Time Machine backup on your machine.
Outlook 2010 on Windows
Microsoft Outlook 2010 has a nifty feature enabling users to create a .pst file to store emails locally on a Windows PC. Microsoft has some instructions on how to do this here:
http://office.microsoft.com/en-us/outlook-help/create-an-outlook-data-file-pst-to-save-your-information-HA010355677.aspx
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