Important: Windows security updates released January 3, 2018, and antivirus software
Overview
Microsoft has identified a compatibility issue with a small number of antivirus software products.
The compatibility issue arises when antivirus applications make unsupported calls into Windows kernel memory. These calls may cause stop errors (also known as blue screen errors) that make the device unable to boot. To help prevent stop errors that are caused by incompatible antivirus applications, Microsoft is only offering the Windows security updates that were released on January 3, 2018, to devices that are running antivirus software that is from partners who have confirmed that their software is compatible with the January 2018 Windows operating system security update.
If you have not been offered the security update, you may be running incompatible antivirus software, and you should consult the software vendor.
Microsoft is working closely with antivirus software partners to ensure that all customers receive the January Windows security updates as soon as possible.
More information
Windows Defender Antivirus, System Center Endpoint Protection, and Microsoft Security Essentials are compatible with the January 2018 security updates and have set the required registry key.
Windows 10, Windows 8.1, Windows Server 2012 R2 and Windows Server 2016 Customers
Microsoft recommends all customers protect their devices by running a compatible and supported antivirus program. Customers can take advantage of built-in antivirus protection, Windows Defender Antivirus, for Windows 8.1 and Windows 10 devices or a compatible third-party antivirus application. The antivirus software must set a registry key as described below in order to receive the January 2018 security updates.
Windows 7 SP1 and Windows Server 2008 R2 SP1 Customers
In a default installation of Windows 7 SP1 or Windows Server 2008 R2 SP1, customers will not have an antivirus application installed by default. In these situations, Microsoft recommends installing a compatible and supported antivirus application such as Microsoft Security Essentials or a third-party anti-virus application. The anti-virus software must set a registry key as described below in order to receive the January 2018 security updates.
Customers without Antivirus
In cases where customers can’t install or run antivirus software, Microsoft recommends manually setting the registry key as described below in order to receive the January 2018 security updates.
Setting the Registry Key
Caution Using Registry Editor incorrectly can cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that problems resulting from the incorrect use of Registry Editor can be solved. Use Registry Editor at your own risk. For information about how to edit the registry, view the “Changing keys and values” help topic in Registry Editor (Regedit.exe) or view the “Add and delete information in the registry” and “Edit registry data” help topics in Regedt32.exe.
Note: Customers will not receive the January 2018 security updates (or any subsequent security updates) and will not be protected from security vulnerabilities unless their antivirus software vendor sets the following registry key:
Key=”HKEY_LOCAL_MACHINE” Subkey=”SOFTWARE\Microsoft\Windows\CurrentVersion\QualityCompat” Value=”cadca5fe-87d3-4b96-b7fb-a231484277cc” Type=”REG_DWORD”
Data=”0x00000000”
Frequently asked questions
Q1: Why are some antivirus solutions incompatible with the January 3, 2018, security updates?
A1: During testing, we discovered that some third-party applications have been making unsupported calls into Windows kernel memory that cause stop errors (also known as bluescreen errors) to occur.
Microsoft has assembled the following resources to help potentially impacted customers:
