Recently, I have had trouble with my wireless, often it will just connect to the local network but not the internet, and I will get a DNS not responding error message when I diagnose the problem in Windows 7.
The only way to fix this has been to unplug the cable modem, and then replug it to the mains to restart it. Is there something wrong with my network adapter or otherwise?

Browse through this link then post back to let me know if it helps you.

kind regards,