Update KB3194496, is not installing correctly and when it fails some machines are forced to restart, often multiple times. Apparently this is because Windows 10 has problems getting rid of the failed update. Worse, after a restart, the file will attempt to install again resulting in the loop of failed install, reboot, re-install and failure again.
Oddly the cumulative update did install correctly on the second or third attempt while others have said that it fails every time.
What is also weird is that the bug was reported before the update was released, but for some reason Vole issued it anyway. It does not bode well for Windows 10, which Vole sells on the basis that its updates are really important and all you every need to think about. Obviously if they tigger your system, you are going to be thinking about them for a long time.