KB5077239

Microsoft has released preview update KB5077239 (build 28000.1643) for Windows 11 version 26H1. Windows 11 version 26H1 received preview update KB5077239 for PCs with ARM64 architecture processors (Snapdragon). Additionally, the update is available for devices with x64 architecture processors (x86-64, Intel and AMD) that have been updated to version 26H1.

• AI Agent in Windows Settings. The agent in the Settings app now supports more languages — support has been expanded for German, Portuguese, Spanish, Korean, Japanese, Hindi, Italian, and Chinese (Simplified). The search results menu now shows more available results, making it easier to quickly find and change settings. A scrollbar has been added to view the full list of results. Recommended settings now apply changes faster — for recently changed parameters, an integrated agent option appears directly in the interface. A dialog box appears if a setting cannot be changed further: it explains the reason and offers an option to adjust parameters if necessary.
• Click to Do. The Click to Do context menu has received a lighter and more intuitive design. It is now easier to access frequently used actions such as copy, save, send and open, and also to find the desired command faster. If a large image or table appears on the screen, the context menu may open automatically, allowing you to perform actions and see the result immediately.
• Camera. Windows Studio Effects can now also be used for an additional camera — for example, a USB webcam or a built-in rear laptop camera. To enable the feature: go to Settings > Bluetooth & devices > Cameras, select the desired camera from the list of connected devices, open Additional camera settings, and turn on Use Windows Studio Effects. After activation, Studio Effects can be configured on the camera settings page or through the quick menu on the taskbar.
• File Explorer. The placeholder text in the File Explorer search box has been updated to highlight the advanced capabilities of Windows Search. Actions in the Home section on hover (for faster file management) are now available to commercial customers.
• Advanced Settings. An option to enable virtual working environments has been added to Advanced Settings. Virtual working environments allow you to enable or disable virtual environments such as Hyper-V and Windows Sandbox. The section is located at: Settings > System > Advanced.
• Continue on another device. Cross-platform resume capabilities have been expanded. You can now continue actions from an Android smartphone on your PC — for example, continue playing Spotify, work in Word, Excel or PowerPoint, and resume a browser session. Users of Vivo Android smartphones can continue viewing websites from the Vivo browser on their PC. If you use an HONOR, OPPO, Samsung, vivo or Xiaomi Android smartphone, you can resume working with online files opened in the Microsoft Copilot app on your phone. On the PC, files open in the corresponding Microsoft 365 app (if installed), otherwise in the default browser. The feature does not support offline files stored only on the phone.
• Windows MIDI Services. MIDI performance in Windows has been improved — expanded support for MIDI 1.0 and MIDI 2.0, including full WinMM and WinRT support for MIDI 1.0 with built-in translation, shared MIDI ports between apps, configurable port names, feedback and MIDI sharing between apps, as well as performance improvements and bug fixes for a smoother musician experience. The App SDK and Tools package is distributed separately. It includes built-in MIDI 2.0 capabilities and tools such as MIDI Console and the MIDI Settings app. Current versions are available on the Windows MIDI Services and GitHub pages and are currently unsigned, which may cause security warnings when downloading or installing.
• Narrator. Narrator now gives you more control over how interface elements are announced. You can choose which details to speak and customize their order to match your navigation style. These settings apply across the app, helping to reduce unnecessary announcements and make speech prompts clearer.
• Voice Access. The initial setup process for voice access has been updated and simplified. The new flow helps you download the appropriate language model, select your preferred microphone, and understand what tasks voice access can perform on your PC.
• Voice Typing. An Action wait timeout parameter has been added — it allows you to adjust the delay before executing a voice command. This helps recognize commands more accurately at different speech tempos, both slow and fast.
• Windows Hello. Windows Hello Enhanced Sign-in Security (ESS) now supports external (peripheral) fingerprint scanners. Previously ESS was only available on PCs with built-in biometric sensors, and now the more secure sign-in option is also available for desktop PCs and other Windows 11 devices, including Copilot+ PCs. To configure, connect a supported ESS reader, go to Settings > Accounts > Sign-in options and register your fingerprint.
• Windows Update. The process of joining the Windows Insider Program has been improved, and situations where the process could hang when connecting via Settings > Windows Update have been fixed.
• Lock screen. Internal changes have been made to fix cases where the lock screen could become unresponsive.
• File Explorer (interface improvements). More consistent dark mode in File Explorer: copy, move and delete dialogs (in both normal and expanded views), progress indicators and chart views have been updated to better match the dark theme and improve readability. Confirmation dialogs (skip, replace, file selection) and several error windows have also been updated for a consistent look. Simplified File Explorer context menu for easier navigation. Frequent actions (e.g., Send, Copy and Move) are grouped in one structured menu. This reduces clutter and makes it easier to find commands when using a mouse, keyboard or accessibility features. Initially this change is available to a limited set of devices while Microsoft evaluates the optimal approach. The Recommended section on the File Explorer home page simplifies access to frequently used and recently downloaded files. To enable this section, you need to activate the Show Recommended section setting in folder options. The feature is available to all users, including those signed in with a personal Microsoft account.
• File Explorer (fixes and improvements). Internal changes have been made to improve File Explorer responsiveness when navigating to network locations. Improved behavior where File Explorer could unexpectedly fail to show thumbnails for video files containing certain EXIF metadata. More stable File Explorer behavior — the toolbar should no longer appear unexpectedly. Fixed: when right-clicking a file, the app icon next to the Open item could display as a standard icon instead of the icon corresponding to the default app for that file type.
• Sign-in. Improved reliability of the scenario where Explorer.exe could hang during first sign-in, which occurred if some apps were configured to start automatically. This could cause the taskbar not to appear.
• Activation. Improved Windows license migration during update. In some cases, a valid license might not carry over because the device did not register the digital license in time — then the activation troubleshooter was required to complete the process.
• Desktop icons. Improved reliability when opening or renaming files on the desktop — icons should stay in place and no longer move unexpectedly.
• Input. Improved display of labels for key repeat delay settings in Settings > Bluetooth & devices > Keyboard.
• User Account Control (UAC). Improved reliability of launching Windows Terminal with elevated privileges from a non-administrator account — the PC should no longer become unresponsive to requests.
• Windows Sandbox. Fixed an issue where Windows Sandbox could hang on startup and show error 0x800705b4.
• Spotlight on desktop. If you use the Spotlight feature as your desktop background (Settings > Personalization > Background), the context menu now includes two items: Learn more about this image and Next desktop background.
• Games. Xbox Full screen experience (FSE) is now available on more Windows 11 handheld devices following its initial launch on ASUS ROG Ally and ROG Ally X. FSE provides a console-like interface with the Xbox app, reduces distractions and improves performance by minimizing background tasks. Enable it via Settings > Games > Full screen mode, where you need to select Xbox as the home app. You can launch it through task view or the game bar, and also configure it to start in full screen mode when the device starts.
• Pen. Pen devices that support haptic feedback can now provide haptic feedback when interacting with the Windows interface — for example, when hovering over the close button, snapping windows or resizing them.
• Keyboard. Improved keyboard backlight performance on supported HID-compliant keyboards. The backlight helps you see keys better in low-light conditions and can adapt to save power. Enabled the AltGr level for the Arabic 101 keyboard layout. The left Alt key works as before, and the right Alt key becomes a modifier for additional symbols. The first new symbol is the Saudi Riyal currency symbol (AltGr+S). It is also available on the currency tab in the on-screen keyboard and in the symbol picker. Switching languages with Alt+Shift is still available via left Alt+Shift or the Windows+Spacebar combination. The Arabic 102 and Arabic 102 AZERTY layouts have been similarly updated.
• Mobile devices settings. A page for adding and managing mobile devices has been added to Settings > Bluetooth & devices > Mobile devices. Here you can manage features such as using your phone as a connected camera or accessing your phone's files through File Explorer.
• OneDrive. A new OneDrive icon is displayed in Settings > Accounts > Home.
• Settings (migration from Control Panel). The key repeat delay and rate settings and the cursor blink rate have been migrated from Control Panel to the Settings app. Key repeat delay and rate are now in Settings > Accessibility > Keyboard, and cursor blink rate is in Settings > Accessibility > Text cursor.
• Settings (About system section). The About system section in Settings has received an updated layout that combines device information and related settings in one place. For example, you can now quickly navigate to storage settings.
• Settings (reliability and interface). Improved reliability when navigating to Settings > Network & Internet — the Settings app should no longer become unresponsive. The search bar in Settings should no longer overlap the Minimize and Maximize buttons in the window title bar.
• Taskbar and system tray. You can now directly share an open app window with Copilot from the taskbar. When hovering over a running app icon, a Share with Copilot option appears — similar to the window sharing feature in Microsoft Teams. Copilot Vision analyzes the window content and provides suggestions based on what is displayed in the app. The Automatically hide the taskbar setting now works more reliably and no longer turns off unexpectedly after the "Toolbar is already hidden on this side of the screen" message. Voice access now responds more reliably when interacting with the taskbar, including selecting items by number. Improved behavior of taskbar icons — when there is free space, icons maintain the expected size.
• Windows Sharing. The drag bar now supports sending multiple files, shows more relevant apps, and simplifies moving files to a selected folder. The drag bar can now be turned on or off in Settings > System > Nearby sharing. The ability to share OneDrive files through other apps has been introduced. Options appear in the Share with list after selecting Copy link. Sign-in with a Microsoft account is required.
• Display and graphics. Improved performance in scenarios where apps request the full list of supported modes from monitors. Previously this could cause brief hangs on very high resolution monitors — changes aim to reduce and prevent such stutters. Improved behavior of the brightness slider on all-in-one PCs — the system better maintains the selected level and helps avoid unexpected brightness changes. Fixed: the Unsupported video card detected message could appear in some games, even when using a supported video card.
• Game Pass. Mentions of Game Pass in Settings have been updated to reflect current branding and benefit descriptions.
• Start menu. For users with the new Start menu, the Windows search bar now matches its size, providing a smoother transition to search.
• Lock screen and sign-in (fixes). Fixed an issue where first sign-in to a new account could be very slow. Fixed a memory leak that could occur when using slideshow mode on the lock screen. Memory leaks over time can lead to performance and reliability issues.
• Smart cards. Fixed an issue where STATUS_NOT_SUPPORTED (0xc00000bb) could unexpectedly appear when signing in using ECC smart card sign-in credentials.

Cumulative update 5077239 for PCs is installed manually via Windows Update. To check for updates, go to Settings > Windows Update and click Check for updates. When you see that the February 2026 Preview Update (KB5077239) (28000.1641) is available, click Download and install. A computer restart is required to complete installation. After the update, the Windows 11 version 26H1 build number will change to 28000.1641.

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