By default, Microsoft Outlook automatically tries to save any e-mail message that you create but do not send. You can return to Outlook later and find the unsent message in the Drafts folder.
In Mail, in the Navigation Pane (Navigation Pane: The column on the left side of the Outlook window that includes panes such as Shortcuts or Mail and the shortcuts or folders within each pane. Click a folder to show the items in the folder.), click Drafts, and then double-click the message.