There is some set of problem with my system. I have a Windows XP with media center installed in the same. I had upgraded the same to Windows Vista. After the upgrade as you know that we have to install all the drivers plus all the needed updates. Once it was done I had downloaded some fresh drivers for Vista. I also found driver for RT73 USB Wireless LAN Card. After installation everything was working except this usb wifi card. It failed to work. I am not able to find any working solution for it.