Windows 2012 Datacenter server (running in a VMware VM) that is also the domain DHCP server. We don't have a secondary DNS server so I'm attempting to add DNS to the current DHCP server. It is not a domain controller.
Looking at the DNS properties page on the Forwarders tab; I'm using the OpenDNS servers and they return <Unable to resolve>. When I saw that those addresses were not resolving, I tried google's DNS addresses in the DNS forwarders list but they too said <Unable to resolve>. I can ping the Open DNS IP addresses, the google DNS IP addresses and the ISP provider's DNS IP addresses, but of course am unable to resolve their respective names.
NOTES:1) I have disabled IPv6 on the DNS' server's Ethernet adapter properties; 2) I have done a flushdns; 3) I have verified that my DNS services are running - and have restarted them a few times; 4) the first DNS on my server's Ethernet adapter properties is the IP address of the DNS server (which is 10.20.0.2) and the second is the loopback (127.0.0.1); 5) nslookup times out regardless of whether I use the OpenDNS or google DNS IPs; 6) I have disabled the firewall (even though it does show DNS allowed through firewall); 7) I removed the Forwarders and tried to use just Root Hints. That didn't make any difference.
A lot of googling has been done, but I've been unable to figure out my misconfiguration. Any help offered will be appreciated and if you need further information, please ask. - Thanks