You delete email all the time, and are probably familiar with the Outlook "deleted items" folder: (deleted items folder)
To clear space for you mailbox (most administrators enforce a size limit) on the mail server, you probably clear this folder routinely. You do this by deleting all items from the "deleted items" folder, kind of like clearing the recycling bin on your file system.
(emptied deleted items)
Clearing Deleted Items, for GoodTo remove the items "for good", go to the Tools/Recover Deleted Items menu option and delete all Outlook documents for a third and final time. The "X" icon takes care of it for you. CYA!