KB5094126

Cumulative update KB5094126 for Windows 11 version 25H2 (2025 Update) was released as part of the June 2026 Patch Tuesday. The OS build after installation changes to 26200.8655. The package is intended for devices based on x64 (amd64) and ARM64 processors and includes all previously released fixes from the preliminary update KB5089573 (Build 26200.8524), as well as new features and security improvements.

• Shared Audio Listening. Added the Shared Audio function, allowing sound to be transmitted simultaneously to two pairs of headphones with Bluetooth LE Audio support.
• Task Manager. Implemented load tracking for the neural processing unit (NPU) and neural engines of the graphics processing unit (GPU).
• Camera. Added support for Multi-App Camera, allowing multiple applications to use the camera simultaneously, and Basic Camera mode for basic debugging.
• Windows Setup. The ability to choose a custom user folder name during the initial system setup stage has appeared.
• Shell Performance. Accelerated launch of applications and basic interface elements, including the Start menu, search, and Notification Center.
• FAT32 Formatting. The volume size limit when formatting via the command line has been increased from 32 GB to 2 TB.
• Fonts. Updated Times New Roman fonts for the Greek and Cyrillic alphabets, improving their display.
• Windows Search. Search now begins to prioritize files already when entering two query characters instead of three.
• Windows Hello. Sign-in using face or fingerprint becomes the default authentication method at every system boot.
• Secure Boot. Added high-confidence targeting data to expand the coverage of devices automatically receiving new Secure Boot certificates. Devices receive certificates only after demonstrating a sufficient number of successful update signals, ensuring controlled and phased deployment. Also added the LimitSecureBootRequiredServiceData group policy to limit the amount of transmitted Secure Boot service data.

This update fixes a virtualization issue that could lead to stop errors HYPERVISOR_ERROR (0x20001) and KMODE_EXCEPTION_NOT_HANDLED (0x1E) after installing the previous cumulative package. Failures occurred on some devices during system reboot, during operations with virtual machines, or when launching certain gaming applications.

Installation of cumulative update KB5094126 occurs automatically via Windows Update. To force check, you need to go to Settings, select the Windows Update section and click the Check for updates button. A computer restart is required to complete the installation, after which the build number will change to 26200.8655.

How the new features work:

Shared Audio Listening: A streaming function has been implemented using the Bluetooth LE Audio protocol and Auracast technology. The operating system acts as a central source, encapsulating the audio stream into Isochronous Synchronization (ISO) packets and broadcasting them simultaneously to two synchronized receivers via the LE Audio class audio driver volume and mixing manager.

Task Manager: Utilization counters for Neural Processing Units (NPU) and GPU tensor cores have been added to the performance monitoring subsystem. The system process tracks machine learning inference task execution through DirectML, querying the Windows Copilot Runtime interfaces to display real-time load on computational units engaged in matrix multiplication and convolution operations.

Camera: Multi-App Camera mode has been added, implemented through the Windows Camera Pipeline framework with video stream demultiplexing at the driver level. This allows multiple applications to capture frames simultaneously without exclusive device locking. Basic Camera mode activates a minimal processing pipeline without post-effects for debugging raw sensor data.

Windows Setup: A user input parser has been implemented in the Out-of-Box Experience (OOBE) configuration module, allowing a custom alias for the profile directory, different from the standard mask based on the account name. The file system creates an NTFS node with the specified name before the first logon session and links it to the user's SID in the registry.

Shell Performance: The launch of Explorer and the Notification Center has been accelerated by introducing a deferred extension loading mechanism and pre-caching resources in memory. Shell Experience Host optimization reduced Start menu rendering delays through asynchronous initialization of XAML UI trees and prioritized fetching of search indices from the local database.

FAT32 Formatting: The artificial volume size limitation of the format.com command-line utility has been removed. Formatting now allows the creation of a FAT32 file system up to 2 TB using 32-kilobyte clusters, which aligns with the limits defined in the BIOS Parameter Block specification but was previously blocked at the code level for volumes larger than 32 GB.

Fonts: The metrics and glyphs of the Times New Roman typeface have been updated for extended Cyrillic and Greek scripts. TrueType contour hinting has been performed to improve readability at low resolutions, and OpenType layout tables (GPOS/GSUB) have been rebuilt for correct positioning of diacritical marks.

Windows Search: The search query tokenization algorithm in the indexer has been modified: the minimum prefix threshold has been reduced from three characters to two. This activates prefetch logic for results from the Search Indexer database at an earlier input stage, using incremental prefix tree analysis for instant ranking of relevant files.

Windows Hello: Biometric authentication via Windows Hello (face/fingerprint) has been set as the default preferred credential provider in the Winlogon mechanism. Upon system startup, the GINA session initiates contactless verification, bypassing the password selection screen, provided a trusted biometric sensor is successfully detected and ready.

Secure Boot: A targeted certificate revocation/issuance system with high-confidence device binding has been implemented in the Secure Boot servicing mechanism. The group policy LimitSecureBootRequiredServiceData has been added to limit telemetry. UEFI certificates are distributed in phases: a device receives an updated db/dbx only after accumulating a sufficient number of successful update signals within its cohort.

Virtualization Bug Fix: A race condition in the hypervisor has been resolved, which led to critical failures HYPERVISOR_ERROR (0x20001) and KMODE_EXCEPTION_NOT_HANDLED (0x1E). The issue occurred due to incorrect access to Virtual Device (VDEV) descriptors when resuming from S-power states and in secondary memory mapping (SLAT) scenarios when launching games with kernel-level anti-cheat drivers.

The last 10 Windows updates: