Running a second copy of the same OS, just for emergencies? My ex-gf has this virus problem (which I asked about in another post) and I realize I have always had dual boot, so I could remove viruses in winxP from my Win98SE. But some of the new av's won't run on win98, and my new computer mobo might not be able to run win98 anyhow, and the question occurs to me, why not have dual boot with another copy of the XP, installed from the same CD with the same product key. Since all the hardware is the same, MS won't even notice, right?? If it did notice, would it object? IIRC the license permits installation on one computer, but doesn't prohibit dual installation on that computer. One could do all his work in the first one and save the other one for times when the first one won't boot. Or is this not worth the effort? Since there are AV Rescue CD's which one boots from and they say they can easily remove the viruses. And maybe all the other boot problems can be solved in Safe Mode.