What is the best practice to do this? Is it better to do an organizational migration in my case? Where can I get a step-by-step guide for an Exchange migration? What "gotchas" should I be aware of? The Exchange 5.5 is running on Server 2000 and the new Exchange 2003 will be running on server 2003.
When you insert the Exchange 2003 CD, it does not run setup directly, but takes you into the Exchange Deployment Tools. These are a cross between a wizard, multiple checklists and a resource library. Note that there is an update to this that came out a few months ago at the same time as SP1; download the AllTools selection under downloads from www.microsoft.com/exchange. You can also run and look at ExDeploy at any time so you can use it to plan and understand your migration. For really great in-depth docs, check out the Exchange 2003 Technical Documentation Library at the same link.
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This was first published in August 2004