Just a heads up. I've been testing this out on my machine and a number of my students' laptops. The new cumulative update (KB4015438) is the death knell for some Dell 9550s. It gives us the absolutely abhorrent, Critical Process Died failure - so bad it doesn't even come with an error code.
Not sure what to do at this point. The update even created a Microsoft System Reserve (MSR) partition on our hard drives, took an hour or so to install, rollback, and reinstall. Even when installed on a completely clean machine, will cause the machine to just *hang* for minutes before blue screening.
I would STRONGLY advise against taking the KB4015438 cumulative update for now if you can. If you cannot, then pray.
Your friendly neighborhood engineer,