This change is workstation, not account specific, so would need to to carried out on all machines that has Outlook installed. However it is possible to enable the 'Recover Deleted Items' menu for all folders via an additional registry key. Therefore if you 'hard delete' items (hold down shift and press the delete key) from one of the other folders, then you cannot recover them, as they haven't been through the 'Deleted Items' folder. However this option isn't available to you by default if you try it with any other folder. If you delete an item from the 'Deleted Items' folder, either by deleting it permanently or emptying the Deleted items folder, then you can get it back by selecting the Deleted Items folder and then choosing Tools, Recover Deleted Items. If your email administrator hasn't enabled it, then you will not have anything to recover. NOTE: Recovery of deleted items in this way is also dependant on an Exchange server setting. Outlook and the command 'Recover Deleted items'.If you hard delete an item from Outlook (shift delete or empty the deleted items folder), then there are two ways to get it back.

Exchange 2010 deleted items recovery