Network Icon Error

I have a 4 computer home network (WIN XP Pro, SP2 fully updated) using a
Linksys Wireless G with Speedboost router WRT54GS with PCI Wireless
G/Speedboost cards WMP54GS in the desktop computers. The network is
controlled by Windows rather than the Linksys utility.

Everything is fine except that in just one of the desktops, the wireless
network icon on the taskbar has begun to show the red X that means that the
network is not connected--- but in fact it is. I'm connected to the
internet-- and can see the other computers. It worked fine for several
months-- but then started giving a false reading. I didn't add.subtract any
software in the computer-- and am fully virus, spyware, firewall protected.

I called Linksys tech support and they said (surprise, surprise) that it's a
Microsoft issue since the icon does not derive from Linksys. They suggested
using the Linksys utility to control the network rather than Windows but for
a number of reasons, I need to use keep using Windows.

I tried updating/reinstalling the card driver-- but no change.

Any ideas?

Savvy