D-Link wireless .... no IP assigned?

I am (was) using a D-Link DWL-G520+ wireless PCI card which is 'refusing'
to allow an IP address to be provided by the main router.
I can't see it being the router is the problem, as it assigns a wireless
laptop an IP without issue, and used to do so with the D-Link.

The D-Link detects a wireless network (the SSID is shown correctly) has the
correct WEP code and MAC codes (for the router config) but connects with
"limited or no connectivity"

TCP/IP config is set to assign automatically. I also assigned manually, and
wireless was then reported as connected, but nothing passed over the
network, i.e. the "page cannot be found", nor could I log into the router.
Hard wired to the router, the PC is fine, and loads web/mail without issue,
so i suspect the wireless card, or maybe a Windows setting although it's set
to use Windows for wireless, and /was/ working.

Faulty card, or a setting somewhere deeper within Windows I need to adjust?