Q. Is there an easy way to clean up the metadata of deleted domain controllers (DCs)?

A. In Windows Server 2008 and later, when you delete a DC from the Active Directory Sites and Services MMC snap-in, all the DC's associated metadata is also deleted. However, on earlier versions of Windows Server, metadata is left around if a DC is improperly demoted.

Microsoft provides a script with a GUI, shown here, to delete DCs.

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