In know your DNS server that's right, see whether they have preferred to your PC set up DNS, ping the domain name, DNS servers are needed to help resolve, if not give PC assigned DNS, it will not be parsed by a domain name, go to ping the domain name will say can not find the host, because it simply can't resolve domain name, of course, also cannot use the domain name to open the url
To sum up, ping domain prompt can not find the host, to see if you have specified DNS to a PC, if specified is wrong, go to the DNS server to see whether the server configuration error