So I have a Windows 8 Pro machine with Media Center (legit key for both) that I'm running as a gaming and multimedia machine. I want to update to the RTM of 8.1 now. Where do I start? I want to preserve all settings and data, and avoid complete reinstallation if at all possible. Thanks, Urbanracer34
What media you'll use for to update? If you use bootable USB Stick or DVD, start the setup from your running windows 8's file manager and follow screen advice. It will tells you what you could keep and what need to new installed.
So in other words you can update from 8.0 Pro WMC (retail) to just 8.1 Pro (retail) and from there to WMC.
Yes, ProWMC is a feature upgrade key, not an install key. It is not intended for straight installs or Windows Upgrades. I'm actually a little surprised that they didn't make a double key verification in 8.1 since regular Pro is required to use the ProWMC key.