I'm running windows 7 without activation. Can I use the Windows 8 Pro Upgrade or do I have to buy something else?
Also I'd like to know in the case that I already had Windows 8.1 Pro WMC (also not activated) installed on my computer, is it possible to use the Windows 8 Pro Upgrade to get a legit copy of windows with or without reinstalling?
To legitimately install W8 Pro upgrade you will have to have had XP/Vista/W7 activated on your PC. If that is not the case you'd best buy the OEM version as you'd have to clean install to a virtually new machine. Unsure about your 2nd question, but I doubt it.
I have found that you can activate W8 Pro Upgrade on a qualifying machine without actually having the OS installed and activated by performing a Refresh immediately after clean installation.
I am unsure as to why you have not activated your copy of Windows 7 in the first place. As far as know it has to be activated and a legit copy in order to upgrade to Windows 8. There again why would you not activate in the first place.