We have currently ran out of the 75GB limit for Stoarge for e-mail. We were told by our CDW rep that there is no upgrade to Exchange Enterprise, so we bought a new license for Exchange Enterprise. We need to convert our Exchange 2003 Stanard to Enterprise. Is it possible install Exchange 20003 Enterprise over Exchange 2003 Standard, or do I need to install Enterpise on a seperate server and migrate the database?