The network is working but I can't get the internet

I checked my internet connection from the modem without the router, make sure that my computer can access the internet when computer is connected directly to modem. But when I use router, the light arte on and I can ping out ( like www.yahoo.com ), but cannot access internet, the screen shows that the connection between modem and router has problem ( X ). very weird? I tried to reconfig three times and no fix this issue.
Please help , or I doubt the D_link router hardware has problem.

Thanks

If the internet is not working first thing to check here is the internet connection from your modem without the router, make sure that your computer can access the internet when computer is connected directly to modem, if no internet without the router you need to contact your ISP for that, but if there's internet without the router you need to reset and reconfigure the router.....if you have the setup CD of the router just run that to reconfigure it back.........