Upgrading from Windows Server 2003 to Windows Server 2008 with Exchange Server 2007
DON'T DO IT!
Doing an in-place upgrade from Windows Server 2003 to Windows Server 2008, on a server where Exchange Server 2007 is installed is not supported.
And it WILL break things.
Your first clue that things will go awry is that you can't do an in-place upgrade when PowerShell is installed. So, if you ignore that clue (what? you need to be hit upside the head with a bat?) and remove PowerShell (can you imagine what removing PowerShell does to Exchange?) - the upgrade will proceed.
And guess what? After you are done, Exchange WON'T WORK.
You'll have a major recovery on your hands to get back to Windows Server 2003. In order to move from Windows Server 2003 to Windows Server 2008, you must use the move-mailbox method of migration.
Until next time...
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