DNS NSLOOKUP

I have my DNS server set up. It allows me to log in to the domain. It also seems to be forwarding request correctly using forwards but when I do a nslookup it always tells me Can’t find server name for address 10.1.10.150 Non existent domain**** default server not available
Default server Unknown
Address 10.1.10.150

Any Ideas why this is coming up????

Everything seems to be working except sending emails using exchange and outlook???