I've been having problems with a clients exchange database doubling in it's size. Originally the size was sitting at about 30-40gb, then one day it just exploded and doubled in size, and this is not due to mail in users mailboxes. With total user mailbox data the Exchange database should actually be between 30-40gb. We've tried defragging the database twice now, the first time we ran the defrag, the size cut about in half from 60gb to 30-35gb. About 3 weeks later the size doubled again to about 60-70gb. After running the defrag again, the size jumped to 90gb+! Can anyone elaborate or help here?