I yesterday bought a brand new Newlink PCMCIA wlan card for use with 1 xp pro sp1 pc and one me one. I brought it home, installed the drivers and the third party wireless manager, but could not connect to my orange livebox. It can see the network, but then the program just keeps saying scanning. The livebox is in pairing mode.
The same is true of the xp pc.
When I use the xp sp1 manager (a simpler one), it tells me there are networks available, asks for the wep key and then fails to connect, it just tells me they are available again.
You really need to use XP with SP2 installed as the SP2 pack contained the much improved WiFi module. Most people recommend the XP WiFi Manager and I have used it for years but not both as they interfere. Generally you can run either the 3rd party wifi manager or XP SP2 WiFi Manager.
It may be your current set up can't find the DHCP addresses and you need to enter them manually.