If you can copy off those emails from the personal folder, then remove that "serivce" all together. Change the location of where "new email is delivered" to the exchange box. Then all the mail, even downloaded via pop, will reside on the exchange server.

The only service we have installed on our outlook clients is the exchange service (and pop on whoever happens to have an external pop address).

When you look in his mailbox, do you SEE 3000 emails? Is that possibly including his contacts, notes, sent items, and journal entries?