Could not see any character after Kodi installation

I have downloaded the Kodi app. and tried to install it. A message popped up asking to firstly install windows 7 platform (KB2670838). So I installed Windows6.1-KB2670838-x64 .
Why it’s written windows 6.1 ?? This was the file I got from microsoft.
After installing Kodi, all characters appeared squares !!!Could not define any setup.
Maybe it happened because I had a Windows 7 Ultimate version ( not legal) ??
Or is it because it was windows 6.1??

Thanks

Eliahu