I have currently bought a new laptop(Window 7) and then share the wireless with my landlord. My laptop shows wireless network is connected but no internet access. However, my landlord use her desktop(apple) in downstair and she can access the internet. I thought is distance problem, I bring my laptop downstair which close with wireless router, but I can't access internet either. Hope anyone can help me, thanks!
Try turning off wireless security in the router temporarily and see if that's the issue -- Apple tend to use different terminology when referring to security types which may have caused confusion. Some older Apple models only support WEP, whereas Windows users tend to apply WPA.
Also check your computer's TCP/IP Properties.
Start, Connect To, Connection, Properties, Scroll Down TCP/IP and highlight, click Properties and check that Obtain DNS and IP address automatically are enabled.