First you have to remember what to recover.
Then highlight : DELETED ITEMS==== then click TOOLS=== then you will get OPTION RECOVER DELETED ITEMS=== then click the ENVELOPE (TO RECOVER).
Also if you have trouble to send Email or Receive Email . Before contacting the the Helpdesk You need the History . If your Email was returning that means it had travelled lots of server . So to get that History how you will get it . What you can do HIGHLIGHT the EMAIL returned then rightclick==== then OPTION=== You will get the Page Message options. There you can see the Header all details History.
Other than that what ever Problem you Face you can see the Following Links for more help.
Micrsoft Outlook Trainings :