January 25, 2008
947282: Error message when you prepare an Active Directory forest for Exchange Server 2007: “Schema update failed”
You run the ForestPrep operation by using the setup.exe /prepareschema command in a Microsoft Windows Server 2003 domain. You do this to prepare a Windows Server 2003 Active Directory directory service forest for Microsoft Exchange Server 2007.
When you do this, you receive the following error message:
Schema update failed: An attribute with the same link identifier already exists
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