Microsoft releases Windows 11 Insider Preview Build 27858 in Canary Channel

On May 16, 2025, Microsoft released Windows 11 Insider Preview Build 27858 to the Canary Channel. Here are the changes and improvements included in the build mentioned on the support page:

[Input]

• We are trying out a new experience to improve the discoverability of the emoji and more panel in Windows 11 with the introduction of a new system tray icon on the taskbar. With this new system tray icon, you can easily express yourself by using emojis, GIFs, Kaomoji etc. across all apps and surfaces in Windows in addition to using the WIN + . keyboard shortcut which is also now shown on the emoji and more panel. This new system tray icon for the emoji and more panel shows can be changed by right-clicking on the icon to go to taskbar settings page.

Fixes: Windows 11 Insider Preview Build 27858

[General]

• Fixed an issue which was causing some Insiders to see a black screen when upgrading to the previous flight.
• Fixed an issue causing text to disappear in places across the system after the previous flight.

[File Explorer]

• As part of our ongoing commitment to improving File Explorer accessibility, this release includes increased support for the text scaling (via Settings > Accessibility > Text size) across File Explorer, File Open/Save dialogs and the copy dialogs.

[Desktop icons]

• Updated the logic for apps pinned to the desktop, so that packaged apps no longer show an accent colored backplate (for example, if you were to drag and drop Snipping Tool from the apps list in Start to the desktop). In doing this, the icons should be bigger and easier to see now. Please note, you may need to create new shortcuts for this to take effect, if you already have something on your desktop.

[Input]

• Fixed an issue where voice typing wouldn’t start from the touch keyboard when using the Chinese (Simplified) narrow layout.
• Fixed a high hitting ctmon.exe crash, which could impact the ability to type.

[Windowing]

• Fixed an explorer.exe crash related to snap layouts which could happen when dragging a window or hovering over the maximize button in a window.

[Taskbar]

• Fixed an issue where the taskbar icons weren’t increasing in size as they should when using your PC in a tablet posture.
• Fixed an issue where when using Hebrew or Arabic as your display language, if you pressed WIN + T then arrow keys, focus through the taskbar icons would move in the opposite direction.

[Graphics]

• Fixed an issue causing night light to not work for some Insiders after the latest flights.
• Fixed an issue which was causing unexpected FPS caps for some Insiders in the previous flight.

[Network]

• Mitigated an issue believed to be the cause of reports that wi-fi stopped working for some Insiders after the previous flight.

[Audio]

• Fixed an underlying issue which could lead to MIDI devices not being recognized in recent Canary flights.

[Other]

• Fixed an issue causing some Insiders to see a bugcheck with KERNEL_SECURITY_CHECK_FAILURE after the previous flight.
• Fixed an issue causing some Insiders to see a bugcheck with SYSTEM_THREAD_EXCEPTION_NOT_HANDLED after the previous flight.
• Fixed an issue where setting your desktop background to a JXR HDR wallpaper wasn’t working for extra wide format (21×9).

Known issues

[General]

• [IMPORTANT NOTE FOR COPILOT+ PCs] If you are joining the Canary Channel on a new Copilot+ PC from the Dev Channel, Release Preview Channel or retail, you will lose Windows Hello pin and biometrics to sign into your PC with error 0xd0000225 and error message “Something went wrong, and your PIN isn’t available”. You should be able to re-create your PIN by clicking “Set up my PIN”.
• [NEW] You may see an Administrative Templates error message when opening Group Policy Editor. If you click OK, you should be able to proceed as normal.

[Input]

• [NEW] Pen input may be non-responsive on some PCs that support pen for inking.

[Task Manager]

• [ADDED] Search and other options such as filtering in Task Manager does not work.

For more information on Windows 11 Insider Preview Build 27858, refer to the support article on the official Windows blog.

If you wish to join the Windows 11 Canary channel and get pre-release builds, you must enroll in the Windows Insider Program and select the Canary channel. However, if you are already an Insider and want to switch from a different channel, like Dev or Release Preview to Canary, you need to do a clean installation of Windows 11.