Windows 10 Version 21H1 Build 19043.928 Business & Consumer Editions

Microsoft announced public release of Windows 10 version 21H1 (Build 19043.928) on May 18, 2021 is the final build for the May 2021 Update.

May 18, 2021 — KB5001330 (OS Builds 19043.928)
This security update includes quality improvements. Key changes include:

- We fixed 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.

- We fixed an issue with security vulnerabilities identified by a security researcher. Because of these security vulnerabilities, this and all future Windows updates will no longer contain the RemoteFX vGPU.For more information about the vulnerability and its removal, see CVE-2020-1036 and KB4570006. Secure vGPU alternatives are available using Discrete Device Assignment (DDA) in Windows Server LTSC releases (Windows Server 2016 and Windows Server 2019) and Windows Server SAC releases (Windows Server, version 1803 and later versions).

- We fixed a potential elevation of privilege vulnerability in the way Azure Active Directory web sign-in allows arbitrary browsing from the third-party endpoints used for federated authentication.

- Security updates to Windows App Platform and Frameworks, Windows Apps, Windows Input and Composition, Windows Office Media, Windows Fundamentals, Windows Cryptography, the Windows AI Platform, Windows Kernel, Windows Virtualization, Internet Explorer, and Windows Media.

- We have resolved an issue where some Insiders were getting an 0x800f081f error when attempting to install an early version of KB5000842. If you continue to hit an issue with the final version of KB5000842 update, let us know via Feedback Hub.





The Windows 10 21H1 feature update is a very small release and does not bring too many new features. However, it does come with performance and security enhancements that will improve the operating system's overall experience, making it worth installing.

The new features in Windows 10 21H1

While a new version of Windows 10 is now available, Windows 10 21H1 is not a very exciting release with many new features.

Instead, it is being released more as a service pack that fixes bugs and includes performance improvements for existing features.

All of the new features in Windows 10 21H1 are instead targeted to business users and the remote workforce. These new features are:

- Windows Hello multicamera support to set the default as the external camera when both external and internal Windows Hello cameras are present.
- Windows Defender Application Guard performance improvements, including optimizing document opening scenario times.
- Windows Management Instrumentation (WMI) Group Policy Service (GPSVC) updating performance improvement to support remote work scenarios.


Writing on the Windows Insider blog, Microsoft announced that Windows 10 Build 19043.928 is the final build for the May 2021 Update.

Microsoft says they will continue to improve the overall experience of the May 2021 Update on customers’ PCs through our usual servicing cadence, meaning some Insiders in the Beta and Release Preview Channels were already testing builds ahead of what will be shipped to consumers, but in terms of the Windows 10 May 2021 Update (version 21H1), Microsoft is already releasing install media on build 19043.928.

The May 2021 Update will be offered to Insiders in the Release Preview Channel via the “seeker” experience in Windows Update at first. This means Insiders will need to go to Settings > Update & Security > Windows Update and choose to download and install 21H1. Once an Insider updates their PC to the May 2021 Update, they will continue to automatically receive new servicing updates through Windows Update (like the monthly update process), including Build 19043.964.

Windows 10 21H1 is a relatively minor update, with the major Windows 10 Update expected later this year with the so-called Sun Valley update to Windows 10.

What’s new in the Windows 10 May 2021 (21H1) Update


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Product: Microsoft Windows 10
Version: 21H1 Build 19043.928.vb_release_svc_prod1.210407-2138 MSDN *
Supported Architectures: 32bit / 64bit
Website Home Page : www.microsoft.com
Language: multilanguage *
System Requirements: PC **
Size: 39.5 Gb