Outlook for 2011 automatically moving messages to on my computer
I had a problem where Outlook 2011 was moving sent and inbox messages from the Exchange folders to the inbox under On My Computer. The solution was to go to Tools -> Mailing List Manager and turn off the rule that must have been set by accident.

If you simply open up the Mailing List Manager I noticed that it automatically creates a rule that matches your email address and then moves them to the Inbox On My Computer. I must have been going through the various menu options and hit return by mistake.