I have a copy of XP bought with the bits with which I made machine A in Jan 2003. (and added SP2). I have a copy of XP bought last week with the bits for another machine (to replace my good lady's died old 98 stager). Let us call this B. I am minded to do a clean re-install on machine A. Can I use the disc which came with B but enter the code key from A? Both XPs are O.E.M. I want to do this because there are certain little wrinkles on the new one which are better than the old one. As e.g. the network wizard is better and also it will save me going through the long rigmarole of having to add SP2.