What does Windows error code 8420 (ERROR_DS_CANT_FIND_EXPECTED_NC) mean?

Status / error code:		Category:

Constant name:
Source:		Operating System:
Description: The expected Active Directory naming context could not be found.

Previous	Next
ERROR_DS_CANT_FIND_DSA_OBJ	ERROR_DS_CANT_FIND_NC_IN_CACHE

ERROR_DS_CANT_FIND_EXPECTED_NC

ERROR_DS_CANT_FIND_EXPECTED_NC (8420) is an Active Directory Domain Services error. The requested directory operation requires a naming context that is not available on the server or cannot be resolved in the current topology. The missing NC can be a domain, configuration, schema, application, or partial replica partition.

What to check

Identify the distinguished name of the expected naming context and the domain controller handling the request.
Verify that the target DC hosts the required replica and has completed replication.
Check for stale topology or a failed promotion, demotion, or partition removal operation.

Useful command

repadmin /showrepl "<DomainController>" /all /verbose

Microsoft: Diagnose AD replication failures · Microsoft: DCDiag · Microsoft: Directory Service system error codes

Looking for a different code? Search another status or error code.