I was seeing this error in Windows update for a few months, and it means no more updates for Windows 8.1 will install until it is fixed. These updates, many of which are security related (one I was missing is an Adobe Flash update for IE), are important and Microsoft has a fix which might work for you:
I’m not writing this post to tell you that, however. You likely already found that link and it didn’t work for you. It sure never worked for me, but this did:
Luckily for us, Windows 8.1 update 1 is the new baseline and a month from now will be required to get any updates. Microsoft has made it very easy to acquire the 6 components of this upgrade and we can install them one-by-one getting us mostly current.
Download all 6 and install them in that order, rebooting if asked (I think that’s 4 times, I lost count). Update: This article on ExtremeTech has links to versions for other architectures as well.
After all that Windows Update should magically be fixed. Many of your missed updates will have been in the rollup package but a half-dozen or so could still be waiting for you. Grab those and hope nothing else goes wrong…