Two PC's connecting - third refuses

Hello everyone

I have a D-LINK Wireless ADSL Router (G-604T).
It has an IP address of 192.168.1.1
It connects nicely to the local DSL line & gives internet access to my Compaq laptop (assigned 192.168.1.5 by the router) and my Desktop (192.168.1.2) but NOT my Dell laptop (assigned 192.168.1.4).
All three PC's was connected fine last night, but when starting my Dell this morning the (new XP SP2 icon) says "limited or no connectivity".
Opening CMD, I try ipconfig/all & a strange IP address of 169.254.52.0 appears.
This confuses me to no extent.
ipconfig?renew does not solve the problem.
Bringing the Dell laptop to a friends house it connects immediately to his network with his IP address.
Coming home - same unknown IP address appears.
Restarting router does not help (but the two other computers connects fine).
My Dell wireless adapter TCP/IP properties is set up to "obtain IP address automatically".

I tried to "use the following IP address" and tried 192.168.1.4 as IP address & 192.168.1.1 as Default gateway. It connects nicely with the Router, but no internet connectivity.

When connecting the Dell to the router via a cable, it works beautifully & connects to the net.

HOW CAN I GET MY DELL TO ACCEPT THE AUTOMATIC IP ADDRESS?????

 

You appear to have a wireless configuration issue. Are you sure the encryption is properly set at both ends? This is the most common reason for failure to connect with WiFi.