Airport to router problem

First - apologies if this has been asked before, but I couldn't find an answer so...

I have been setting up a new iMac (17" dual core) for a friend.
Because there is no direct phone socket on it! I have had to set him up with a wireless network. No problem normally, but..
I have the router configured, the Mac says that the ethernet port is connected to the internet via the router, Airport (built in) says it's connected via WLAN - the routers default name, green lights all round then, but it won't load a single web page. I can just access the routers set up and that's it!

Any help will be gratefully received. I'm really stuck! Probably missing some silly setting, but I know Airport is fickle at times.
There is no security on the connection either, so it's not that.
Thanks in advance!

The first thing I'd check would be your DNS and DHCP. Go to System Preferences > Network. Change Show: to be AirPort then click the TCP/IP button. Does everything look right there?

opus_az said:

The first thing I'd check would be your DNS and DHCP. Go to System Preferences > Network. Change Show: to be AirPort then click the TCP/IP button. Does everything look right there?

Click to expand...

My wireless network system is working well so I went to check my wireless network configuration and it is as what is said above.

Does your router have a ping feature? Can you ping, say, 64.119.32.100 from your computer or the router?

Thanks guys. I don't think it is that - he has a dynamic ip, but i'll be looking tomorrow. Thanks again.

Silly question, but you DO have the wireless router hooked up to the Internet somehow, right?

I only ask because you said the iMac had no phone socket, so that means your friend is using dial-up. I'm just wondering how you plan on connecting the router to a dial-up connection.