My dell laptop says it is connected to the wireless network

My dell inspiron 1545 says it is connected to our wireless internet (routed from a cable connection) but when you try to open the internet it says "Internet Explorer cannot display the webpage." I tried going to many different websites but after this initial page they go to "Web address is invalid." The router works on all other devices in the house (ipod touches, other computers) just not the dell laptop. It is an N router and my computer has a g-card in it but the router settings are set to allow g devices to access it. I've also tried the Run+cnd+ping google and yahoo to no avail. I also got an N adapter USB thing which doesn't help either.

Any idea?

Please help.

Thanks!

I didn't find the right solution from the Internet.

References
en.community.dell.com/support-forums/network-internet-wireless/f/3324/t/19340849

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