This one says "You need to install .NET framework 3.5, which comes with Windows, but isn't installed by default."
In Windows 8.1, press the Windows key (on your keyboard - the one that looks like a flag between the Ctrl and Alt keys), type the word "features" and after the search is done, you will see "Turn Windows Features On or Off". Click that.
Next, scroll through the list (actually, it's at the very top). Click ".NET Framework 3.5 (includes .NET 2.0 and 3.0)". Then click OK.