Applies ToWindows Server version 1909 Windows 10, version 1909, all editions

Release Date:        1/21/2021

Version:                 OS Build 18363.1350

12/8/20 Adobe Flash Player went out of support on December 31, 2020. For more information, see Adobe Flash end of support on December 31, 2020. Adobe started blocking Flash content from running in Flash Player on January 12, 2021. For more information, see Adobe Flash Player EOL General Information Page.

12/8/20 REMINDER Windows 10, version 1903 reached end of servicing on December 8, 2020. To continue receiving security and quality updates, Microsoft recommends that you update to the latest version of Windows 10. If you want to update to Windows 10, version 1909, you must use the Enablement Package KB4517245 (EKB). Using the EKB makes updating faster and easier and requires a single restart. For more information, see Windows 10, version 1909 delivery options

11/19/20 For information about Windows update terminology, see the article about the types of Windows updates and the monthly quality update types. To view other notes and messages, see the Windows 10, version 1909 update history home page.

Note Follow @WindowsUpdate to find out when new content is published to the release information dashboard.

 Highlights

  • Updates an issue with some special key combinations used in DaYi, Yi, and Array IMEs that might cause an application to stop working.

  • Updates an issue that prevents you from opening a document that is on the Windows desktop and generates the error, “The directory name is invalid.”

  • Updates an issue that displays a blank lock screen after a device wakes up from Hibernate.

  • Corrects historical daylight savings time (DST) information for the Palestinian Authority.

  • Adds a notification that tells you when your device is close to end of service (EOS). At EOS, your device will stop receiving important quality and security updates.

  • Updates an issue that fails to show Extract all on the shortcut menu when you right-click an online-only ZIP file. 

Improvements and fixes

This non-security update includes quality improvements. Key changes include:

  • Enables administrators to disable standalone Internet Explorer using a Group Policy while continuing to use Microsoft Edge's IE Mode.

  • Enables you to configure certain policies that support Microsoft Edge IE Mode using mobile device management (MDM).

  • Addresses an issue that displays a User Account Control (UAC) dialog box unexpectedly when you turn on speech recognition.

  • Addresses an issue that fails to notify the target application when you select the Copy link command on the Share menu.

  • Changes the way DirectX 12 runtime components load by splitting the d3d12.dll binary into two pieces: d3d12.dll and d3d12core.dll. This change improves versioning and updating for these components.

  • Addresses an issue that prevents JumpList items from functioning. This occurs when you create them using the Windows Runtime (WinRT) Windows.UI.StartScreen API for desktop applications that are packaged in the MSIX format.

  • Addresses an issue that occurs when the Mandatory Profile check box is selected when you copy a user profile.

  • Addresses an issue with some special key combinations used in DaYi, Yi, and Array IMEs that might cause an application to stop working.

  • Addresses an issue that prevents you from opening a document that is on the Windows desktop and generates the error, “The directory name is invalid.” This issue occurs after changing the desktop location in the Location tab of the Desktop Properties dialog box (File Explorer > This PC > Desktop).

  • Addresses an issue that displays a blank lock screen after a device wakes up from Hibernate.

  • Corrects historical daylight savings time (DST) information for the Palestinian Authority.

  • Addresses an issue with German translations of Central European Time.

  • Adds support for serial number control using the registry.

  • Addresses an issue that causes the upload of diagnostic logs to a management service, such as Microsoft Intune, to fail. The failure occurs because of a network time-out on a slow network.

  • Displays a notification to a user when an administrator signs in to an MDM service, such as Microsoft Intune, to find the location of a managed device.

  • Addresses an issue that causes the silent mode deployment of BitLocker to fail with the error 0x80310001. This issue occurs when deploying BitLocker encryption to Hybrid Azure Active Directory (Azure AD) joined devices.

  • Addresses an issue that causes an unexpected system restart because of exception code 0xc0000005 (Access Violation) in LSASS.exe; the faulting module is webio.dll.

  • Addresses an issue that might cause systems that use BitLocker to stop working with the error 0x120 (BITLOCKER_FATAL_ERROR).

  • Addresses an issue that causes a device to stop working when deploying Microsoft Endpoint Configuration Manager if AppLocker is enabled on the device.

  • Addresses an issue that might cause a black screen to appear or delay signing in to Hybrid Azure Active Directory joined machines. Additionally, there is no access to login.microsoftonline.com.

  • Addresses an issue that cause the LSASS.exe process to leak memory on a server that is under a heavy authentication load when Kerberos Armoring (Flexible Authentication Secure Tunneling (FAST)) is enabled.

  • Addresses a memory leak on Windows servers that are configured as Active Directory domain controllers. This issue occurs when the Key Distribution Center (KDC) attempts to fetch the Service for User (S4U) client name during certificate authentication.

  • Addresses an issue that causes LSASS.exe to stop working because of a race condition that results in a double free error in Schannel. The exception code is c0000374, and the Event Log displays Schannel event 36888, fatal error code 20, and error state 960. This issue occurs after installing Windows updates from September 2020 and later.

  • Addresses an issue in which a principal in a trusted MIT realm fails to obtain a Kerberos service ticket from Active Directory domain controllers (DC). This occurs on devices that installed Windows Updates that contain CVE-2020-17049 protections and configured PerfromTicketSignature to 1 or higher. These updates were released between November 10, 2020 and December 8, 2020. Ticket acquisition also fails with the error, “KRB_GENERIC_ERROR”, if callers submit a PAC-less Ticket Granting Ticket (TGT) as an evidence ticket without providing the USER_NO_AUTH_DATA_REQUIRED flag.

  • Addresses an issue with HTTP caching that interferes with kiosk mode that targets Azure AD groups.

  • Addresses an issue with using Windows Defender Application Control (WDAC) and running a file while Managed Installer (MI) or Intelligent Security Graph (ISG) is enabled. You can now use fsutil to look for the $KERNEL.SMARTLOCKER.ORIGINCLAIM extended-attribute (EA) on a file. If this EA is present, then MI or ISG can run the file. You can use fsutil in conjunction with Enabling ISG and MI diagnostic events.

  • Addresses an issue that allows an app that has been blocked from hydrating files to continue hydrating files in some cases.

  • Addresses an issue that prevents access to a Volume Shadow Copy Service (VSS) snapshot of Resilient File System (ReFS) volumes for 30 minutes. This occurs when the ReFS volumes contain 100,000 or more concurrently open files. As a result, a time-out occurs, which causes backups of the first and third applications to fail.

  • Adds a notification that tells you when your device is close to end of service (EOS). At EOS, your device will stop receiving important quality and security updates.

  • Addresses an issue with Administrative Template settings you configure using a Group Policy Object (GPO). When you change the value of the policy settings to NOT CONFIGURED, the system continues to apply the previous settings instead of removing them. This issue occurs after installing the June 2020 or later updates and is most noticeable with roaming user profiles.

  • Addresses an issue that fails to show Extract all on the shortcut menu when you right-click an online-only ZIP file.

  • Updates the process for enrolling in online speech recognition. If you are already enrolled, you will see a message that asks you to review the new settings. If you choose not to contribute your speech data for human review, you can still use online speech recognition. The new settings contain one button to turn on online speech recognition and another button that turns on the collection of your voice clips. If you turn on the collection of your voice clips, you can turn it off at any time using the same button in the new settings page.

If you installed earlier updates, only the new fixes contained in this package will be downloaded and installed on your device.

Windows Update Improvements

Microsoft has released an update directly to the Windows Update client to improve reliability. Any device running Windows 10 configured to receive updates automatically from Windows Update, including Enterprise and Pro editions, will be offered the latest Windows 10 feature update based on device compatibility and Windows Update for Business deferral policy. This doesn't apply to long-term servicing editions.

Known issues in this update

Symptom

Workaround

Microsoft and Discord have found incompatibility issues with some games using Direct3D 12 when the in-game overlay feature of Discord is enabled. When attempting to open affected games you might receive an error, or the game might close silently.

To mitigate this issue, you can turn off the in-game overlay in settings within the Discord app.

This issue is now resolved in an update to the Discord app. To verify you're on the latest version, right click on the Discord icon in the notification area and select "Check for updates...". If there are updates to install, it should install automatically but you might need to select the arrow icon in the upper right corner of the app to install the updated version. There is no update for Windows needed to resolve this issue.

You might receive stop error 0x7E in nwifi.sys with a blue screen when you attempt to use a Wi-Fi Protected Access 3 (WPA3) connection. You are more likely to encounter this issue when reconnecting to a Wi-Fi network after disconnecting or when waking from sleep or hibernation. 

Note Most Wi-Fi networks are currently using WPA2 and are not affected.  

To mitigate this issue, you can do one of the following: 

  • Update your device to Windows 10, version 2004 or Windows 10, version 20H2.

  • Connect to a Wi-Fi network using WPA2. To do this you may need to reconfigure your access point or router settings.

  • Connect using a wired ethernet connection.

This issue is resolved in KB5001028

How to get this update

Before installing this update

Microsoft strongly recommends you install the latest servicing stack update (SSU) for your operating system before installing the latest cumulative update (LCU). SSUs improve the reliability of the update process to mitigate potential issues while installing the LCU. For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

If you are using Windows Update, the latest SSU (KB4598479) will be offered to you automatically. To get the standalone package for the latest SSU, search for it in the Microsoft Update Catalog.

Install this update

Release Channel

Available

Next Step

Windows Update or Microsoft Update

Yes

Go to Settings Update & Security > Windows Update. In the Optional updates available area, you’ll find the link to download and install the update.

Microsoft Update Catalog

Yes

To get the standalone package for this update, go to the Microsoft Update Catalog website.

Windows Server Update Services (WSUS)

No

You can import this update into WSUS manually. See the Microsoft Update Catalog for instructions.

File information

For a list of the files that are provided in this update, download the file information for cumulative update 4598298

Note Some files erroneously have “Not applicable” in the “File version” column of the CSV file. This might lead to false positives or false negatives when using some third-party scan detection tools to validate the build. 

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