Update 27th April 2012. Although Outlook allows you to add @wbs and @warwick to a whitelist these are automatically removed after a short period of time. Hence these instructions likely will not help with internal emails. You can still use these instructions however to whitelist the addresses of any external contacts.

Outlook 2010 includes its own anti-spam system that is not managed centrally. You may find that legitimate messages are sometimes moved to your Junk e-mail and should therefore check it regularly. By default any message in your 'Junk e-mail' folder will be permanently deleted after 30 days.

You may wish to change the settings on your 'Junk e-mail' folder, or even to turn it off. This support page shows you how to make such changes.

• Ensure you are in the mail view by clicking 'Mail' in the Notification area
  
  
• In the 'Delete' section on the ribbon toolbar click the 'Junk' option and select 'Junk e-mail options'
  
  
• You will see that the default setting is 'Low' such that only the most obvious junk e-mail is directed to the Junk E-mail folder. You can vary this by selecting High (nearly all junk e-mail will be moved to the folder but so will some legitimate messages' or 'No Automatic Filtering'. Personally I'm not making any changes to my settings yet although I do wish to add some addresses and domains to the whitelist. To do this click the 'Safe senders'tab.
  
  
• Click Add and enter any individual addresses or domains you wish to whitelist. For example you may wish to add, '@mail.wbs.ac.uk' (our student email system). Unfortunately it is not possible to add either wbs.ac.uk or warwick.ac.uk (although Outlook does not tell you this is a problem). Click OK twice to close the open dialogue boxes.
  

In future no messages from these domains should go to your Junk e-mail folder although keep checking.. I haven't found it to be perfectly behaved