Hi Reacher. I don't know the answer to your question, so to push you back to the top of the page, I'll just give my opinion instead. If you are happy with Win 2000, I think you should leave things as they are. If you are seriously thinking about upgrading to XP, then back up everything before installing the evaluation software. I certainly wouldn't risk a stable set up by trusting any software to uninstall properly. I think that after the 120 day trial you will have to use the Microsoft uninstall utility to remove XP yourself.