These steps can be only performed if you have ADMIN Right on your PC.
1) Go to the RUN from startup and Type regedit
2) Expand the HKEY_Local Machine ->Software -> Microsoft -> Exchange ->Client ->Options
3) Click on the Options
4) List of three items will be opened to the right hand side with three fields Name, Type & Data
5) Imply Right click below the three items
6) New’ option will be opened
7) Select the “DWORD value” and a new list will be created
8) Rename the file to be “DumpsterAlwaysOn” ( note that D , A & O are in caps)
9) Double click on the new file(DumpsterAlwaysOn)
10) A menu will be opened, now give the value data =1 and select the hexadecimal
11) Now restart the Outlook and click on the place from where u need to recover
12) For ex : click on Inbox or sent items from where u need to actually recover the mail.
13) Now go to “Tools” from outlook and select the “Recover Deleted mails”