Thanks for your patience. We’re putting Hiding the “Conversation History” folder (and other empty, unused folders) under consideration, for possible Outlook.com improvements.Rachael commented
I need to hide or get rid of the following folders: Archive, Conversation History, RSS Subscriptions, Search Folders. It's as if every few days, another mysterious folder appears in my list. I don't have room or patience for this. I have a hundred other folders that I actually use. Give us this option, already. If you can add them for no apparent reason, you can easily give us the option to remove them. Try making your customers happy for once. This isn't hard...