You need to know which drive the email file was stored on and then you need to ensure that no file operations (create, delete, copy etc) are carried out on the drive. Any file activity on the drive will reduce your chances of successful recovery. If you only have one drive on the pc you should remove it and connect it to another pc to avoid it getting written to. Then download a copy of recuva (free) from here:
At the time of Hard- deletion, there is no way to retrieve Outlook emails because Scanpse.exe doesn’t work in high level corruption. At that time, you should move on a third party utility like- SysTools Outlook recovery software, its provides you free-trail version facility which helps you to recover 25 items per folder and show preview of all recovered data.
When an user account has been deleted from Outlook its files don’t get automatically removed. For removing them you have to manually delete each and every email of that particular account or if you define and rule for particular accounts email to dropdown in a particular folder then the task become easy as you have to delete that folder only.