Had this one through this morning when i switched on (my updates auto-check).
https://support.microsoft.com/en-gb/help/4524147/windows-10-update-kb4524147
but it didn't auto down and install, like the bottom of that article says it should.
Mine looks like this now :-
so, do i have to click on download, and do it manually (as i can't even do a check for updates now with the Yellow Triangle there), but i don't fancy doing that though, as ive just read that it breaks the Start Menu for some, and fails to install for some, Critical Errors, oh eck, what to bloody do!