KB5089549


Microsoft released cumulative update KB5089549 for Windows 11, versions 24H2 / 25H2 as part of the May 2026 Patch Tuesday. The cumulative update package KB5065426 (Build 26200.8457 / 26100.8457) is intended for Windows 11, version 25H2 (Windows 11 2025 Update) on x64 (amd64) and ARM64 processors.

The update includes various security improvements for internal OS features from May 2026, and also includes all fixes and changes from the KB5083631 (Build 26200.8328) Preview update for Windows 11, version 25H2.

Known issues: In May 2026, Microsoft fixed 120 security issues. Among the fixed bugs are issues with Kerberos authentication in Remote Desktop via Remote Credential Guard and the RDP security warning dialog when working with multiple monitors of different scaling.

Also fixed is a BitLocker bug that caused some devices to enter BitLocker recovery mode after updating boot files on systems with incorrect PCR7 configurations (this issue was observed after installing KB5083769 from April 2026).

Increased reliability of Simple Service Discovery Protocol (SSDP) notifications to prevent the service from becoming unresponsive.

If you have installed previous updates, only the new updates contained in this package will be downloaded and installed on your device. A computer restart is required to complete installation. After the update, the Windows 11 build number will change to 26200.8457.

Installation via Windows Update: cumulative update 5089549 for PCs installs automatically through Windows Update. To check, go to Settings > Windows Update and click Check for updates.

Feature / Change Performance Increase / Decrease Optimization PC Speed Gaming Optimization
Xbox Mode for laptops, desktops, and tablets 🟢 Increase (+10–20% in supported titles) 🟢 High — system resource allocation prioritized for games 🟢 Faster during gaming sessions 🟢 Critical — smoother gameplay on any device type
Support for uu, cpio, xar, and NuGet (nupkg) archives ⚪ No impact 🟡 Medium — built-in extraction reduces third-party tool load ⚪ No change ⚪ Not applicable
Haptic feedback for compatible pens and mice ⚪ No impact 🟡 Low — tactile feedback may improve input precision ⚪ No change 🟡 Low — minor immersion benefit
Redesigned voice input on touch keyboard ⚪ No impact 🟢 Medium — better dictation flow reduces correction time 🟡 Slightly faster text input ⚪ Not applicable
New agent tracking mechanism on taskbar 🟡 Small decrease possible (background agent load) 🟡 Medium — dynamic assistant agents streamline workflows 🟡 Neutral to slight slowdown on low-end devices ⚪ Not applicable
Increased FAT32 formatting limit to 2 TB via command line ⚪ No impact 🟢 Medium — faster large-volume formatting workflows ⚪ No change ⚪ Not applicable
Updated driver security policy 🟡 Minimal impact (driver validation overhead) 🟢 High — blocks malicious cross-signed drivers ⚪ No change 🟢 Medium — cleaner driver environment for games
Protected batch file processing mode ⚪ No impact 🟢 High — prevents command substitution attacks ⚪ No change ⚪ Not applicable
Additional data for Secure Boot ⚪ No impact 🟢 High — broader automatic certificate rollout ⚪ No change ⚪ Not applicable
Increased Boot Manager reliability 🟢 Slight increase (fewer recovery interruptions) 🟢 Medium — avoids BitLocker recovery delays 🟢 Faster, more stable boot ⚪ Not applicable

Find and Change Settings

Setting Where to find How to change
Xbox Mode for laptops, desktops, and tablets Settings > Gaming > Xbox Mode Open Settings > Gaming > Xbox Mode and turn the feature on to optimize system resource allocation for smoother gameplay. Turn it off to restore default resource management.
Support for uu, cpio, xar, and NuGet (nupkg) archives in File Explorer File Explorer > Select archive file Open File Explorer and double-click or right-click a supported archive (.uu, .cpio, .xar, .nupkg). Use the Extract command in the ribbon or context menu to open and extract contents without third-party software.
Haptic feedback for compatible pens and mice Settings > Bluetooth & devices > Pen & Windows Ink
Settings > Bluetooth & devices > Mouse
Open Settings > Bluetooth & devices > Pen & Windows Ink and enable haptic feedback for a compatible pen. For a compatible mouse, open Settings > Bluetooth & devices > Mouse and turn on haptic feedback or adjust intensity if available.
Redesigned voice input on the touch keyboard Touch keyboard > Microphone key Open the touch keyboard and tap the microphone key to start dictation. The new interface shows improved speech recognition visualization automatically. No additional settings are required.
New agent tracking mechanism on the taskbar Taskbar > Taskbar settings
Microsoft 365 Copilot > Researcher
To manage dynamic assistant agents on the taskbar, right-click the taskbar and open Taskbar settings. Enable or disable agent icons under the taskbar items section. The Researcher agent in Microsoft 365 Copilot uses this mechanism automatically when available.
Increased FAT32 formatting limit to 2 TB via command line Command Prompt > format command Open Command Prompt and use the command: format /FS:FAT32 . FAT32 partitions up to 2 TB can now be created instead of the previous 32 GB limit.
Updated driver security policy Local Group Policy Editor > Computer Configuration > Windows Settings > Security Settings > Local Policies > Security Options Open the relevant security policy for driver signing and enable trust revocation for cross-signed drivers. To disable this protection, set the policy to Disabled or Not Configured.
Protected batch file processing mode Registry Editor > HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager Create or modify the DWORD value LockBatchFilesWhenInUse under the Session Manager key. Set it to 1 to block modifications to .bat and .cmd files while running. Set it to 0 to disable protection.
Additional data for Secure Boot Settings > Windows Update > Update history This data is applied automatically through Windows quality updates. To check installation status, go to Settings > Windows Update > Update history and verify that the latest quality update is installed successfully.
Increased Boot Manager reliability Settings > Windows Update > Update history This improvement is applied automatically after installing the update. No manual configuration is required. Devices should boot normally without entering BitLocker recovery mode.

Official announcement on the Microsoft website.

The last 10 Windows updates:

Update Build Version Windows Channel Date
KB5121132 28120.2760 26H1 Windows 11 Experimental 2026-08-21
KB5124040 26220.9223 25H2 Windows 11 Beta 2026-08-21
KB5124042 26340.9233 26H2 Windows 11 Experimental 2026-08-21
KB5121106 28020.2731 26H1 Windows 11 Beta 2026-08-17
KB5121109 28120.2738 26H1 Windows 11 Experimental 2026-08-17
KB5124036 26220.9202 25H2 Windows 11 Beta 2026-08-17
KB5124038 26340.9212 26H2 Windows 11 Experimental 2026-08-17
KB5120996 28000.2796 26H1 Windows 11 Preview 2026-08-14
KB5120998 26200.9267 25H2 Windows 11 Preview 2026-08-14
KB5120240 22631.7517 23H2 Windows 11 Stable 2026-08-11