Wireless networks available but cannot see any in the XP Wireless networks window

Hi,

I am having a problem with a Toshiba SP A10 and external wireless cards. It seems that I am unable to use the Windows Wireless configuration when I have any WIFI card installed. I can access the networks tru' the WIFI cards s/ware but when I check the 'Use Windows to configure....' in the advanced settings it tells me there are networks available but does not display them. I really need to use the Windows config as the laptop is used by different people and the config. for the cards is pretty cumbersome compared to the Windows wireless config. Any ideas would be appreciated. I have tried DLink and Trendnet cards both with the same results.
Thanks in anticipation.