Hello William,
Thank you for your prompt reply.
I appreciate your patience.
For KB3000850 update issue, please refer to suggestions from UweFurchheim replied on November 21, 2014 and check if it helps.
For KB2934520 update issue, I would suggest you to run .NET framework cleanup tool and then try to install the update.
Please refer this link:
http://blogs.msdn.com/b/astebner/archive/2008/08/28/8904493.aspx
(Holds good for Windows 8.1)
I hope this information helps.
Thank you