Wireless internet connection detected, but not working?

[geronimo]

I just installed a new router (wireless internet connection). Everything is going very smoothly. On my mac, I have the proxy settings set to automatic. My cousin's laptop is vista, and it detected the connection and connected, and it says that it's connected with all the green bars and stuff. The problem is that the internet won't work on his laptop, web pages can't be opened. I figure it's something wrong with the proxy settings, but it's also set to automatic. I'm stumped. Could any one please help.. details are more than welcome!
Thank you!

[2008]

You can't set the proxy in auto mode, because it will uses the proxy instead of the regular internet connection.