have you tried rebooting your router?
Last resort, you can try this:
1. Unplug the network cable, turn off the router/modem.
2. Hit Win-R, type 'cmd' and hit enter (or Start > Run > All programs > Accessories > Command prompt)
3. Type 'ipconfig /release' (without quotes) and hit enter
4. Type 'ipconfig /flushdns' (without quotes) and hit enter.
5. Type 'netsh winsock reset' (without quotes) and hit enter.
6. Type 'netsh int ip reset c:\resetlog.txt' (without quotes) and hit enter
7. Type 'netsh int reset all' (without quotes) and hit enter
8. Type 'netsh routing reset all' (without quotes) and hit enter
9. Type 'netsh routing dump' (without quotes) and hit enter
10. Plug in network cable and turn router/modem back on.
11. Wait 5 minutes.
12. Type 'ipconfig /renew' (without quotes) and hit enter.
13. Check connection status again. It should say 'Connected'.