By default, the Outlook folder list groups similar folders, such as inboxes, from all of your mail and Microsoft Exchange accounts. This feature can make it easier to read all your messages at once, without having to move around between mail folders. If you want, you can turn off this feature so that each account and all its folders are separated in the folder list.

On the Outlook menu, click Preferences

Under Personal Settings, click General

Under Folder list, clear the Group similar folders, such as Inboxes, from different accounts check box

Applies To: Outlook for Mac 2011, Outlook for Mac 2013, Outlook for Mac 2014