Once you have deleted an email from your inbox and emptied your recycle bin, there is a way to restore one or more emails.
1. In Outlook, click on Deleted Items
2. On the ribbon at the top of the screen under the Home tab, click on Recover Deleted Items From Server
OR you can right click on Deleted Items and select Recover Deleted Items
3. Once inside Recover Deleted Items, you can either restore emails or purge emails. Select the email that you want to restore, choose Restore Selected Items, click Ok. Your email will be restored to your Deleted Items.