The Navigation Pane appears on the left side of the Outlook window and is how you switch between the different areas of Outlook, such as Mail, Calendar, Contacts, Tasks, and Notes. In addition, when you're working within a view, the Navigation Pane displays the folders within that view.
When you select a folder in the Navigation Pane, that folder becomes the active folder and you can work with the items within it. For example, in Mail, select the Inbox folder to see new email messages.
Switch between Mail, Calendar, Contacts, and Tasks using the Navigation Pane
The bottom of the Navigation Pane contains the buttons that enable you to switch between Mail, Calendar, Contacts, Tasks, Notes, Folder List, and Shortcuts.
Depending on your Navigation Pane options, you might see icons or buttons at the bottom of the Navigation Pane.
Customize the Navigation Pane
You can customize how the buttons at the bottom of the Navigation pane appear. For more information, see Change the buttons on the Navigation Bar.