Sorry if you've read something similar to this a million times but I can never understand what's going on.
I have a Macbook Pro with Leopard X.
My house has a Belkin wireless router (N-Wireless router) and though my AirPort always has a full network connection, I can never hold on to an internet connection for the life of me.
I have the correct password (given by landlady) so I know that's not the problem.
When I connect directly to the hub (Ethernet cable, like right now) I always have a perfect connection.

Is there some kind of driver software I need to download in order to be able to interface with the router?

I had the same Belkin router running a wifi network with a Mac Mini, a Powerbook, 2 palm LifeDrives and a PC. When I added a MacbookPro it just would not log on. But it could log onto a neighbour's network (with his permission) using a Netgear DG834PN router. So I went out and bought one and it works perfectly with all my machines. It just seemed to be some subtle incompatibility between the MBP Airport card and the Belkin. That was over a year ago so I would have thought Apple might have sorted out a fix for the popular Belkin router by now. You might check Apple support before you spend on a new one.

Good luck

I am not familiar with your specific router, but the 802.11n draft standard is not supposed to come out until 2010, and that is still a draft and not the final standard. In the meantime manufacturers, including Apple, have been building and releasing devices based on what each believes the draft standard, and hopefully the final standard, will be. There is a large body of agreement on the draft so there is a lot of compatibility, but the devil is in the details. As a result not all 802.11n devices are compatible with one another.

So it is entirely possible your landlady's Belkin router may work well with one computer but not another. There is nothing you can change in your Mac either hardware or software that will solve that incompatibility. The 802.11n draft standard does provide for an 802.11b/g compatibility mode. I honestly do not know if that would help in your case or not, but it would be worth talking to your landlady to see if the compatibility mode is turned on.

I agree with Joe. There may be something wrong with the router settings. My Belkin N1 handles three computers, a Wii and an iPod Touch without a hitch. Recently, I changed my old G4 PowerBook for a new MBP and there was not a slightest problem. If the router is in your apartment, you can log on to it and check the wireless settings for yourself. It may also help if you check the "IPv6 off".
Please tell us how it goes.
P.S. Unfortunately, many of us have experienced the situation when Airport shows 4 bars but there is no connection. I could never get a straight answer to this...

There is no secret to that the network power indicator on the menu bar lies.

Seriously, if I want an accurate reading of WiFi signal strength I use AirRadar. There are other similar products but this one has worked well for me.