Hello mginster-0346,
Thank you for posting in our Q&A forum.
1.What did you mean "anything imported via lgpo"?
2.Would you please check whether any other local policy is applying over domain GPO? Or only the following two domain GPO settings is applying over domain GPO?
Admin Templates - System - Remote Procedure Call - "Enable RPC Endpoint Mapper Client Authentication" and "Restrict Unauthenticated RPC Clients"
If the two local group policies and other local policies are all applying over domain GPO, maybe it is related something imported via lgpo.
If only the two local group policies you mentioned are applying over domain GPO, I suggest you can try to troubleshoot the issue using process monitor and analyze what process changes the setting.
https://learn.microsoft.com/en-us/sysinternals/downloads/procmon
Hope the information above is helpful.
Best Regards,
Daisy Zhou
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