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Announcing Windows 10 Insider Preview Build 21387

Written By published May 21, 2021

Hello Windows Insiders, today we are releasing Windows 10 Insider Preview Build 21387 to Windows Insiders in the Dev Channel.

Changes and Improvements

Fixes

  • We fixed an issue in the previous flight where during the upgrade and in the welcome screens displayed after first sign in, the text was unexpectedly using the Times New Roman font.
  • We fixed an issue resulting in some Insiders seeing errors when trying to launch Notepad via the Run dialog.
  • We fixed an issue for WSL users, preventing some Linux GUI apps from launching correctly via the shortcut that is automatically added to Start menu.
  • We fixed an issue resulting in the reset or change PIN workflows not working.
  • We fixed an issue where for some Insiders, night light was immediately turning off after being enabled.
  • We fixed an issue in recent flights where you might unexpectedly get a “We can’t find an audio device” error when trying to play audio from a connected Bluetooth speaker.
  • We fixed an issue where explorer.exe might crash after repeated use of the touchpad gesture for switching Virtual Desktops.
  • We fixed two issues impacting the ability to print using USB printers.
  • We fixed an issue resulting in the Windows Update page potentially becoming unresponsive after clicking Pause Updates.
  • We fixed an issue causing some devices to fail with error code 0xc1900101. While this fix will resolve the problem on some devices, there is a second issue causing the same error code (noted below). We’re working on a fix for this issue as well.
  • We fixed an issue where some devices were re-offered the .NET update after it is installed. After taking this build you should no longer be reoffered the .NET update. If you experience and issue getting Build 21387 because of a pending .NET update, you can work around the issue by pausing then un-pausing updates.
  • We fixed an issue where some devices would crash with a DPC_WATCHDOG_VIOLATION error when using OneDrive Personal Vault.
  • We fixed a ctfmon.exe crash when using ATOK (a third-party IME) if reconversion was triggered in some win32 apps.

Known issues

  • The Windows Camera App currently does not respect the default brightness setting set via the new Camera Settings page.
  • We’re investigating an issue where elements of Search (including the search box in File Explorer) are no longer displaying correctly in dark theme.
  • [News and interests] We’re investigating an issue where the flyout may occasionally flash in the top left corner of your screen after clicking the button on your taskbar.
  • We’re working on a fix for a second issue causing some devices to fail when updating to this build with error code 0xc1900101. When the update fails, it will roll back to the previous build. If you are encountering this issue, we recommend pausing updates until we release a build with the fix.

Important Insider Links

You can check out our Windows Insider Program documentation here, including a list of all the new features and updates released in builds so far. Are you not seeing any of the features listed for this build? Check your Windows Insider Settings to make sure you’re in the Dev Channel. Submit feedback here to let us know if things weren’t working the way you expected.

If you want a complete look at what build is in which Insider channel, head over to Flight Hub. Please note, there will be a slight delay between when a build is flighted and when Flight Hub is updated.

Thanks,
Amanda & Brandon

Tags:
Windows Insider Program