Can't perform an NSLookup to domain controllers from member servers.

Hi,

I have a couple of member servers in the domain, which cannot do an nslookup of either of my 2 DCs in the domain. However, some other member serverscan do an NSLookup on both domain controllers.

I have checked ipv4 settings on all the member servers (those which are working ok and which have this problem). The DNS servers are set correctly and can be pinged from every server.

I have restarted the NETLOGON service on both domain controllers to ensure the SRV records are registered correctly.

The forwarders and adapters in DNS Server settings are set correctly.

Any help much appreciated.