Something nasty went out from Windows Update a few days ago. KB3045999 wouldn't install. I couldn't run some Java stuff, updated Java and still no joy. After a bit of effort, Acronis got me back to pre-that bad update. I then waited for a couple of days and lo and behold, the total size of the update changed, then changed again. I then re-updated and all was fine.
Only happened on one of my machines though!