I've taken the plunge and reinstalled XP Pro and SP2 on one of my laptops. Then I installed the Prolific Serial Cable Driver before anything else. The RS232 to USB cable now works! However I now have to have a laptop for each USB RS232 device! I will load the rest of my usual software (less any other known user of the same driver) and see how I get on. I'm currently downloading an enormous number of XP updates (40 at the last count)!