Microsoft released the October 2019 optional monthly Windows 10 “C” release cumulative updates with KB4520062 being the most noteworthy as it fixes an issue leading to a black screen being displayed at startup during the first sign in after installing an update.  […]

from https://www.bleepingcomputer.com/news/microsoft/windows-10-1809-update-kb4520062-fixes-a-startup-black-screen-issue/