Windows 7 computers that are not running compatible antivirus software are no longer receiving security updates from Microsoft due to a compatibility issue that causes BSODs.
The policy was originally introduced in Windows 10 with the January 2018 cumulative updates. Microsoft required Windows 10 systems to set a special registry key to continue receiving security updates, with incompatible antivirus software blocking any patches released by the company.
Windows 7 systems without antivirus or with security products that are not considered compatible are also excluded from receiving security updates.
Unlike Windows 10, Windows 7 does not come with built-in security software, and the software giant is offering Microsoft Security Essentials for free to those who have not yet upgraded to a newer version of the operating system.
To set the registry key that Microsoft checks when sending new updates, you need to follow the following path and then create a new DWORD (32-bit) entry and name it cadca5fe-87d3-4b96-b7fb-a231484277cc with a value of 0:
Computer \HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat
As for the list of security products that may not be supported, thus preventing Windows 7 systems from receiving updates, Microsoft does not provide any relevant guidance.
Industry leaders have already updated their security software to comply with the new Windows 10 policy, so it's likely that the same will apply to Windows 7. In short, the majority of antivirus products should be technically compatible with the 2009 operating system.
Windows 7 will continue to receive updates until January 2020, and it is critical for systems still running this version of the operating system to install the latest patches as soon as possible.
