if it has failed and it cannot be used anymore you can just remove it using
NTDSUTIL.
With that you can cleasn its AD metadata
also look at:
MS-KBQ216498_How to remove data in Active Directory after an unsuccessful
domain controller demotion
if that DC hosted other roles, make you you won't experience issues. For
example if it hosted DNS, WINS, DHCP...
For both DNS/WINS: point servers to other DNS/WINS servers and change DHCP
scope accordingly to provide new DNS/WINS servers
For DHCP: setup new DHCP server with scopes
etc
etc.
etc.
--
Cheers,
(HOPEFULLY THIS INFORMATION HELPS YOU!)
# Jorge de Almeida Pinto # MVP Windows Server - Directory Services
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