If you download the 'wushowhide' from this link…
I've been following this thread because my father's machine is having this problem. The machine restarts by itself to install KB4056892. My father has had to run a System Restore several times already!
I downloaded and ran wushowhide.diagcab as you suggested, and hid KB4056892. After
it finished running, I checked the Windows updates, and alas specific update is downloading again.
Will it merely download but be suppressed, or will it download and install?
EDIT: KB4056892 has finished downloading and installing. So, we don't want to restart the computer, because it will mean going through the whole System Restore nonsense yet again. I just don't know how to stop it from installing!