Question : Windows XP Wireless Networks Unavailable?

Help! I am fixing an issue on Toshiba Qosmio Laptop, WXP Media Centre where the wireless adapter was picking up Belkin wireless router for about a week and then stopped. The view wireless networks window says No Available Networks when the laptop is right beside the router.
The drivers have been replaced and properties say that device is working properly, 2 infections were removed with Eset Smart Security and an sfc /scannow was performed.
The adapter switch is in the ON position and lit although the FN/F8 toggle does not display anything on screen to say on or off.  I replaced this utility from the Toshiba CD but no difference.  I am at a loss!

Answer : Windows XP Wireless Networks Unavailable?

Thanks all for your interest and suggestions, however I have not been back to the site and will have to abandon this question.