After 5 weeks of having to wait for my computer to stop because it was installing some pending updates, and failing each time (0x80070663)... and of trying to update it going to Windows update, and trying to update it by downloading the KB files directly, I came to CodeProject and made the question and in less than one hour phil.o gave me an answer that solved my issues.
Here, I'm posting that answer in order to make it easier for me to find it again and of course to help anyone with the same issue,
How To Solve It
Before you start modifying the register and getting mad, it's worth trying to use the simple Microsoft fix it that solves the Windows Update problem which can be found here:
EXE FILE LINK ==> http://go.microsoft.com/?linkid=9779673&entrypointid=MATSKB
PAGE WHERE THE EXE FILE IS PLACED ==> https://support2.microsoft.com/default.aspx?scid=kb;en-us;290301
In my case, executing the Fix It assistant made it, and as it was a Windows Update issue, I selected "the program doesn't appear on the list".