Recommended USB-RS232 driver

My XP home edition upgrade does not have a USB-RS232 adapter driver for use with the programming kit. I tried downloading a driver from one site; the driver installed fine and showed up as a COM port in the Hardware Device List but did not work. (BTW, port was correct, cable connected and all powered on). Is there a site that provides a driver certified by Vex?

**The easyC Programming Kit has a driver included with the kit. We also use the USB to Serial Adapter from Radio Shack. This unit comes with a CD that has a proper driver on it to be installed. **