One Outlook user claims to have not seen one mail message. It is not in any of his mail folders, not in the deleted folder, not in the list of recoverable deleted items (items held by exchange after deletion).
It is really not in his mailbox. Checked on OWA, (and on another workstation using Outlook 2003 with a different login).
Exchange message tracking tells me that the message was delivered to his mailbox.
His mailbox is not full or even very large, he deletes his completed mail.
It was delivered yesterday, well within the Exchange recovery interval, and there are older items in his recoverable email list.
There aren't any relevent rules shown, (looking through Outlook Web Access).
Outlook 2007, Exchange 2003 SP2 (6.5.7638)
What can you do in Outlook 2007 that has the effect of removing a message from your mailbox, without leaving it in the recoverable deleted items? Where has it gone?