RBF sounds right. Also check the number of days to save old and new messages in the system setup menu (or is it cos?). Anyway, there are only 255 available message pointers or *slots* per mailbox to hold messages. Just because you delete a message doesn't mean it's gone or that *slot* is freed to take a new one until the "days to keep messages" expires.(just like cinderella, almost all vm processes that stuff at midnite).