A migration is when the new product is installed on another computer and information is moved to the new computer, with little or no impact to users.
A transition occurs when information is exported from one version of a product and then imported into another installation of the product (whether it be the same or a later version).
Using a series of simple questions, the EDA prepares a customized set of instructions for a given scenario.
As a broad overview of the steps to be accomplished for an Exchange migration, it's a good start.
Following the instructions in the KB, enable Integrated Windows Authentication on the Microsoft-Exchange-Active Sync directory.
The Exchange setup process checks these things too, but it's best that you verify them for yourself, so that when setup throws an error it doesn't come as a surprise. You can't have any Exchange 2000 servers and all Exchange 2003 servers must be at SP2. To verify whether Exchange is in Native Mode, open the Exchange System Manager (ESM), right-click the Exchange Organization name in the selection pane, and select properties.I was lucky enough that one of my partner companies, Clark Systems Support, allowed me to do their migration, and I based this article on my experience there.Exchange Deployment Assistant Microsoft has recently made a new tool, the Exchange Server Deployment Assistant, available at technet.microsoft.com/exdeploy2010.You can also use ESM to see the versions of the Exchange servers you have in your organization, as Figure 2 shows.If your ESM is configured to display Administrative Groups (like in Figure 1), you'll need to expand the Administrative Groups node, then expand the node containing your historical administrative group (AG).