Microsoft says Microsoft Defender Advanced Threat Protection (ATP) might stop running on Windows 10, version 1809 devices after installing the KB4520062 Cumulative Update. Windows Defender Antivirus is not affected by this issue, Microsoft says. Windows 10 Health Dashboard says black screens are displayed at startup during the first sign in after installing an update. Microsoft says there is no workaround available for those who have already installed the update and no security mitigations were pushed with it, uninstalling it should fix the issues it causes.
Source: https://www.bleepingcomputer.com/news/microsoft/windows-10-kb4520062-update-may-break-microsoft-defender-atp/