If your organization is using an Microsoft Exchange server, then Exchange Server stores deleted emails for a length of time, and its called the Retention Period. Exchange Administrator can set the retention period, before exchange server permanently deletes the emails.
The Exchange servers have a Retention Period of 60 days.
Below steps will explain how to recover deleted Emails from Microsoft Outlook. You can recover deleted emails from Deleted Items folder in MS Outlook. But if you deleted emails permanently then how to recover it?
Open Microsoft Outlook 2013 and Navigate to Folder->Recover deleted items,
Select Emails which you want to Recover & click on Recover button as shown in below screen shot.
Now recovered Email will be available in Inbox folder in Microsoft Outlook 2013.