I have been running XP in Parallels for several years. In January I tried to upgrade to Windows 8. The installation failed, Microsoft tech support couldn't figure out why, so they refunded my money and I forgot about it. Two weeks ago, I tried again and it failed again. Again, tech support couldn't figure it out, but they guy asked me a nagging question. Are you running an anti-virus program? I said no because I had forgotten about PC Shield Deluxe, which I thought I had disabled long ago. This time they talked me into changing my purchase from download to disk. I waited patiently for 1.5 weeks for the DVD to arrive. Using the physical disk was no better. The upgrade would start, then stop and vanish without a word. Then the nagging question resurfaced. So I went through the whole sequence of uninstalling the anti-virus stuff, which indeed was OFF, and tried again. Lo! Windows 8 installed itself and kept all my user files from XP - although it took 2+ hours to do it. Then it invited me to install the "free" update to 8.1. I clicked YES, but it said: Hold on. I first have to install 90 updates to Windows 8, estimated time 4 hours. That's grinding away right now. All this time and expense is to run one program, that can't run under XP, to monitor and update my CPAP machine, when plugged in as a USB device. Hmmm. Maybe I'll submit a claim under Obamacare. What could go wrong?