Microsoft latest 'Patch Tuesday' update has an issue on devices with Sophos Endpoint Protection installed and managed by either Sophos Central or Sophos Enterprise Console (SEC) that may cause a system to freeze or hang upon restart after installing this update.
Users of Avast for Business and CloudCare have been reporting machines locking up on start-up and Avira antivirus users are suffering from Windows running very slowly.
It appears that many Windows versions are affected by the update problems -- Windows 7, Windows 8.1, Windows Embedded 8, Windows Server 2008, Windows Server 2012, Windows Server 2012 R2 and Windows 10.
Microsoft has temporarily blocked devices from receiving these updates if the Sophos Endpoint is installed until a solution is available.
If you have already installed the Patch Tuesday updates, you should boot your computer into safe mode and roll back the updates. Sophos recommends that you disable the Sophos antivirus service (and 'tamper protection' if enabled) after booting into safe mode, then reboot normally and uninstall the relevant updates before re-enabling Sophos antivirus.