Why was this question closed: https://superuser.com/questions/223366/can-ping-ip-address-and-nslookup-hostname-but-cannot-ping-hostname-closed ? Please reopen it since it hasn't been fixed yet.
Your question was not closed. It was migrated to another StackExchange site called ServerFault. Here's the new link to your question:
For future reference, questions regarding Server operating systems and enterprise-level networking are not appropriate for the SuperUser environment. Please post such questions to ServerFault instead. SuperUser is intended for questions about Workstation operating systems and Small Office/Home Office (SOHO) networks.
That leads immediately to the question why the hint and link that it is migrated isn't at the top of the page, but at the bottom– bernd_kDec 26, 2010 at 10:22
If you look at the stated reason for close you will see that it was migrated over to serverfault.