Double helpings:
I have had the same problem with those last 3 Updates for Win 8.1 64 Bit Version: there's a link underlined in blue "Trouble shoot problems with updates" - it installs Powershell and fixes the issues, but there seems to be a prob where updates are installed; but the associated registry entries are corrupted.
The Windows fix installed the updates KB2976536 and the two others. [Edit: I had two lots of installs - but the prob was resolved when I cold re-booted] I've never used this utility before.
I do not know if the problem was specific to my set up - but clicking the link is worth a try. Win 8.1 Users I have installed KB3008627.
It was a big optional update. I installed on the 11/11/2014.
CAT III