The servers that your computer is getting from DHCP might not be correct or it is just not available. What you can do is manually type in a DNS server into the network configurations in windows.
1. Go to Start and select the Control Panel.
2. Select Network and Sharing Center.
3. On the left pane, click on Change Adapter Settings.
4. Right-click on your network adapter and select properties(there might be more than one, but choose the one that says Local Area Connection).
5. Click on Internet Protocol Version 4 (TCP/IPv4) and then click on properties.
6. On the bottom half of the window you will see and option that says Use the following DNS server addresses. Click the button to select that option.
7. Enter the address 126.96.36.199 into the Preferred DNS server box (this is a Google public DNS server which I happen to use as well)
8. Optional - In the Alternate DNS server box you can enter 188.8.131.52 (this is another public DNS server.)
This is a valid DNS configuration that I happen to use myself.