To enable Deleted Item Recovery on mail folders other than Deleted Items (such as Sent Items, Drafts, Outbox, and Inbox), the following registry entry needs to be made:
Add the DWORD value DumpsterAlwaysOn =1 to the following registry key of the administrator's Outlook client
1. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Client\Options
This can be done either at the administrator's computer or the user's computer. After this value is added, the Recover Deleted Items option becomes available for all the other mail folders mentioned earlier. The user can recover deleted items from these folders. This procedure can become tedious if it is done on all user workstations. An easier solution is to make this registry modification on the administrator's computer and then have the administrator open the affected user's mailbox as an additional mailbox. The administrator can then recover deleted items from the user's mailbox mail folders.