Applies ToWindows 10, version 2004, all editions Windows Server version 2004 Windows 10, version 20H2, all editions Windows Server, version 20H2, all editions

Release Date:

3/9/2021

Version:

OS Builds 19041.867 and 19042.867

EXPIRATION NOTICE

IMPORTANT As of 9/12/2023, this KB is only available from Windows Update. It is no longer available from the Microsoft Update Catalog or other release channels.  We recommend that you update your devices to the latest security quality update. 

2/24/21 IMPORTANT As part of the end of support for Adobe Flash, KB4577586 is now available as an optional update from Windows Update (WU) and Windows Server Update Services (WSUS). Installing KB4577586 will remove Adobe Flash Player permanently from your Windows device. Once installed, you cannot uninstall KB4577586. For more details about Microsoft’s plans, see Update on Adobe Flash Player End of Support.

11/17/20

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 2004 update history home page.

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

Highlights

  • Updates to improve security when Windows performs basic operations.

  • Updates to improve security when using Microsoft Office products.

  • Updates security for the Windows user interface.

Improvements and fixes

Note To view the list of addressed issues, click or tap the OS name to expand the collapsible section.

  • This update makes quality improvements to the servicing stack, which is the component that installs Windows updates. Servicing stack updates (SSU) ensure that you have a robust and reliable servicing stack so that your devices can receive and install Microsoft updates.

This security update includes quality improvements. Key changes include:

  • This build includes all the improvements from Windows 10, version 2004.

  • No additional issues were documented for this release.

This release also contains updates for Microsoft HoloLens (OS Build 19041.1140) released March 9, 2021. Microsoft will release an update directly to the Windows Update Client to improve Windows Update reliability on Microsoft HoloLens that have not updated to this most recent OS Build.

This security update includes quality improvements. Key changes include:

  • Addresses an elevation of privilege security vulnerability documented in CVE-2021-1640 related to print jobs submitted to “FILE:” ports. After installing Windows updates from March 9, 2021 and later, print jobs that are in a pending state before restarting the print spooler service or restarting the OS will remain in an error state. Manually delete the affected print jobs and resubmit them to the print queue when the print spooler service is online.

  • Security updates to the Windows Shell, Windows Fundamentals, Windows Management, Windows Apps, Windows User Account Control (UAC), Windows Virtualization, the Windows Kernel, the Microsoft Graphics Component, Internet Explorer, Microsoft Edge Legacy, and Windows Media.

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

For more information about the resolved security vulnerabilities, please refer to the new Security Update Guide website.

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

When using the Microsoft Japanese Input Method Editor (IME) to enter Kanji characters in an app that automatically allows the input of Furigana characters, you might not get the correct Furigana characters. You might need to enter the Furigana characters manually.

Note The affected apps are using the ImmGetCompositionString() function.

This issue is resolved in KB5005101.

After installing this update, you might receive an APC_INDEX_MISMATCH error with a blue screen when attempting to print to certain printers in some apps.

This issue is resolved in KB5001567.

When opening a document in Microsoft Word, Microsoft Excel, or any Microsoft Office applications, you might receive the error, "Microsoft Excel cannot open or save any more documents because there is not enough available memory or disk space". This issue only affects devices that have installed Microsoft Office apps from the Microsoft Store and are attempting to open a document that has triggered the use of the Protected View feature.

This issue is resolved using Known Issue Rollback (KIR). Please note that it might take up to 24 hours for the resolution to propagate automatically to non-managed devices. Restarting your device might help the resolution apply to your device faster. For enterprise-managed devices that have installed an affected update and encountered this issue, it can be resolved by installing and configuring a special Group Policy.

Note Devices need to be restarted after configuring the special Group Policy. To find out more about using Group Policies, see Group Policy Overview.

After installing updates released March 9, 2021 or March 15, 2021, you might get unexpected results when printing from some apps. Issues might include:

  • Elements of the document might print as solid black/color boxes or might be missing, including barcodes, QR codes, and graphics elements, such as logos.

  • Table lines might be missing. Other alignment or formatting issues might also be present.

  • Printing from some apps or to some printers might result in a blank page or label.

This issue is resolved in KB5001649.

How to get this update

Before installing this update

Prerequisite:

Microsoft now combines the latest servicing stack update (SSU) for your operating system with the latest cumulative update (LCU). If you encounter the error, 0x800f0823 – CBS_E_NEW_SERVICING_STACK_REQUIRED, close the error message and install the last standalone SSU (KB4598481) before installing this LCU. You will not need to install this SSU (KB4598481) again for future updates. 

For general information about SSUs, see Servicing stack updates and Servicing Stack Updates (SSU): Frequently Asked Questions.

Install this update

Release Channel

Available

Next Step

Windows Update and Microsoft Update

Yes

None. This update will be downloaded and installed automatically from Windows Update.

Microsoft Update Catalog

No

No longer available.

Windows Server Update Services (WSUS)

No

No longer available.

If you want to remove the LCU

To remove the LCU after installing the combined SSU and LCU package, use the DISM/Remove-Package command line option with the LCU package name as the argument. You can find the package name by using this command: DISM /online /get-packages.

Running Windows Update Standalone Installer (wusa.exe) with the /uninstall switch on the combined package will not work because the combined package contains the SSU. You cannot remove the SSU from the system after installation.

File information

For a list of the files that are provided in this update, download the file information for cumulative update 5000802

For a list of the files that are provided in the servicing stack update, download the file information for the SSU - version 19041.860 and 19042.860

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