Please follow these steps:
1)On a clean WinXP machine, only install WiFi driver.
2)Verify if Windows wireless utility is in control. If not.....continue
3)Go to Windows Services and verify that 'Wireless Zero Configuration' service is running. If not, start the service and modify its startup type to 'Automatic'.
4)Now go to bottom right corner of your desktop window and 'dbl-clk' on windows networking icon. This will pop-up a new window. If you are not able to see wireless scan list, clk on 'Change Advanced Settings' in the Left pane.
5)You will see a networking properties window with 3 tabs. Clk on 'Wireless Networks' and enable 'Use Windows to configure my......' check box. clk OK.
6)Now you should be able to use Windows utility.