Windows 7 computers that aren't running compatible antivirus software not any longer receive security updates from Microsoft due to a compatibility issue that's considered as causing BSODs.

This insurance policy was originally introduced on Windows 10 with your January 2018 cumulative updates. Microsoft required Windows 10 systems align a dedicated registry get into order to continue receiving security updates, with incompatible antivirus software blocking any patches which the company released.

As documented in Myce, Windows 7 systems without antivirus or with security things that aren't considered to be compatible can be blocked from getting security updates.

Unlike Windows 10, Windows 7 doesn't always come with built-in security production, therefore the software giant offers Microsoft Security Essentials totally free to those who haven't yet upgraded for a newer version of the software.
"The magic registry setting"

Setting the registry key that Microsoft checks whenever shipping new updates, you should navigate to the following path and thereafter create a new DWORD (32-bit) entry and name it cadca5fe-87d3-4b96-b7fb-a231484277cc with value 0:

Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat

With regards to the list of security products that might not be supported and as a result prevent Windows 7 systems from receiving updates, Microsoft itself doesn't provide any guidance as this one.

But the industry leaders possess updated their security software to agree to the new Windows 10 policy, and then the chances are that exactly the same thing applies to Windows 7 far too, so the a lot of antivirus products should technically be that will work with the 2009 os already.

Windows 7 continue receiving updates until January 2020, and it's crucial for systems still running this form of the computer system to install the hottest patches without delay.

Microsoft recommends customers on Windows 7 to make the upgrade to Windows 10 already, specially in the case of enterprises while process is complex and involves additional steps.