Servers which allow send and receive of emails without connecting online are called as Exchange Dedicated servers. Email can be send from one server to another without being connected online. These servers are setup on Windows Dedicated servers. The migration process from Exchange server 2003 to Exchange server 2007 is an important process. Some of the important points and the two types of migration process are given below : 1) It is not possible to move Exchange server on Windows 2003, to move upto Windows server 2008. 2) Clustered mailboxes are not possible to move and this is due to Fail Over Cluster setup. 3) Without upgrading Exchange Server It is not possible for you to upgrade Stand-alone Server to Windows 2008 Serve. 4) Recovery features cannot be used while upgration. 5) By pre-installing server and migrating data on to it, Exchange Server can be moved from Windows Server 2003 to Windows Server 2008. 6) This process also includes replication of mailboxes, folders, data. 7) We will not have to manually modify the files If we migrate on pre-installed server. It also reduces downtime. 9) In terms with cluster servers, it is important that we keep the existing data and remove any third-party applications, Exchange and then upgrading the Windows Server 2003 to Windows Server 2008. 10) All pre-requisites should be fulfilled while migrating from one operating system to another. 11) Maintaining the data depends on the number of servers in cluster. 12) Move all mailboxes to another server and then uninstall Exchange, in the case of multiple mailboxes. 13) It is important to uninstall Exchange and Windows Powershell from passive node in cluster. 14) We have to check all tasks for all server nodes. 15) It is important that we recognize server role. 16) Windows Server 2008 with Exchange Server 2007 should be planned. 17) Same version of Exchange Server 2007 should be runned on EdgeSync process. 18) Edge Transport Servers subscribed to Active directory. 19) Exchange Server 2007 does not have cross-operating system. Windows Exchange Dedicated Servers are normally setup on Cluster servers.