Recover deleted items from microsoft exchange mailbox

From CASwiki

On an exchange mail account to show a "recover deleted items" menu option in the tools menu.

http://office.microsoft.com/en-us/outlook/HA011165281033.aspx

Exit Outlook. Open the Windows registry editor.

Browse to My Computer\HKEY_LOCAL_MACHINE\Software\Microsoft\Exchange\Client\Options.

On the Edit menu, point to New, and then click DWORD Value.

Type the name DumpsterAlwaysOn.

Note Do not type any spaces in the name.

Set the DWORD value to 1.

Restart Outlook.

The Tools menu now has the Recover Deleted Items command for every Outlook folder.