By default, Outlook 2010 creates an "RSS Feeds" folder which cannot be deleted in the usual way you would delete a folder.
I want to remove the folder, so I read How to Remove RSS Support from Outlook and discovered the MFCMapi gem of a utility. I followed the instructions in the section "Delete the RSS folder using MFCMAPI" section, and was able to remove the folder from Outlook.
However, the "RSS Feeds" folder now shows in the "Deleted Items" folder in Outlook Web Access (OWA) and also on my mobile devices, but not in Outlook. In OWA I attempted a right-click and delete, but I am told that folder cannot be deleted. I poked around my OST file (I am running in cached exchange mode) using again using MFCMapi to see if I could find the folder but I do not see it. Finally I created a new Outlook profile in which I do not cache messages, so I could get a "live" look at the server and attempt to see the folder and delete it that way, but it still did not show.