Deleting an inbox

Deleting an inbox

We originally connected teaminbox to an inbox that had been running for 3 plus year. There were in excess of 100000 emails in this inbox and this has caused n end of problems. We are now looking to disconnect this inbox and connect up a fresh one. My only concern is, what will happen to all of the emails that have been assigned and all of the responses that have been sent? I want to delete the inbox but retain that important information. Anyone know?