Low success rate of active name resolution

Copper Contributor

We are getting the following errors on some ATP connected DC's.

The official Microsoft documentation is telling us to open NTLM, NetBIOS an RDP ports for the Defender for Identity Sensors. 


My understanding is that we need to open these ports on all other servers/clients for the DC that is receiving the error.


For example if our dc is we will have to open the NTLM, NetBIOS and RDP port on all devices for

1 Reply
Hi there,

First of all, did you manage to resolve this issue? If so, it would be great if you could share detail of what you did to fix it?

Secondly, if this is still a problem for you, could you please share some detail on the errors you are seeing? I can't see any description of errors in your original post other than Low success rate of active name resolution.

Many thanks