ERROR_DS_DUP_RDN 0x800720BA

Error code 8378 · HRESULT 0x800720BA

WINDOWS

Schema update failed: duplicate RDN.

Windows troubleshooting diagram: Device Manager warning and a system file scan
Windows errors: check drivers, system files and Event Viewer, in that order.

What it means

ERROR_DS_DUP_RDN is a Windows error code (system error 8378, returned as HRESULT 0x800720BA) reported by Windows. Its official message is: “Schema update failed: duplicate RDN.”

How to fix ERROR_DS_DUP_RDN

  1. Reboot once — many one-off system codes disappear with a clean restart
  2. Repair system files: 'sfc /scannow' then 'DISM /Online /Cleanup-Image /RestoreHealth'
  3. Find the source in Event Viewer → System: filter for this exact code and open its provider link

Related errors

ERROR_DS_DUP_OIDERROR_DS_DUP_MAPI_IDERROR_DS_DUP_SCHEMA_ID_GUIDERROR_DS_DUP_LDAP_DISPLAY_NAMEERROR_DS_NOTIFY_FILTER_TOO_COMPLEXERROR_DS_SUBTREE_NOTIFY_NOT_NC_HEADERROR_DS_CANT_DEL_MASTER_CROSSREF

Source: Microsoft WinError.h

Last updated: