Windows 10 build 21390 drops in the Dev Channel

Microsoft releases a new preview of Windows 10 (build 21390) with new icons and the option to set Windows Terminal as the default experience for PowerShell and Command Prompt.

Windows 10 build 21390
Windows 10 build 21390
  • Windows 10 build 21390 is ready for download in the Dev Channel.
  • This build introduces new icons for Task Manager and MSI installers.
  • You can now set Windows Terminal as the default emulator for Command Prompt and PowerShell.

As part of the ongoing development of the Sun Valley update (version 21H2), Microsoft is now rolling out Windows 10 build 21390. This is preview number 76 releasing to testers and is a minor update with various improvements and fixes.

According to the company, build 21390 introduces a new icon using the Fluent Design language for Task Manager and MSI installers. Also, you can now set Windows Terminal as the default emulator for Command Prompt and PowerShell so that when you try to open one of the consoles, it will default to the Terminal experience. (This requires Windows Terminal version 1.9 to work.)

See also this video highlighting all the new changes in this build.

As for fixes, Windows 10 build 21390 addresses problems with punctuations in Chinese, svchost.exe crashes, Start reliability, Task Manager showing the incorrect icon for some processes, fixes error code 0xc1900101 updating to the latest build, and more.

Known issues with build 21390

Microsoft is also pointing out several issues with build 21390, including:

  • The Camera app does not respect the default brightness setting set available on the new Camera Settings page.
  • Windows Search elements no longer display correctly in the dark theme.
  • The “news and interests” taskbar widget has an issue that may occasionally flash in the top left corner of your screen after clicking the button on your taskbar.

Microsoft is listing the complete set of improvements, fixes, and issues for Windows 10 Insider Preview build 21390 at the Windows Blog.

Download Windows 10 build 21390

The build 21390 preview is available immediately through the Dev Channel, and it will install automatically. However, you can always get it manually from Settings Update & security > Windows Update and clicking the Check for updates button.

You can learn more about all the changes available in the current development process of Windows 10 in this guide.

Update June 7, 2021: Microsoft is now rolling out Windows 10 build 21390.1000 as update KB5004071. However, this update does not bring anything new. Instead, it’s an update to test the deployment of cumulative updates with the operating system. Furthermore, the company also notes that every week, followed by a build release, it’s going to push similar updates to continue testing the update mechanism.

Update June 10, 2021: The software giant has now made available the build 21390.1010 as the update KB5004092 to test the servicing pipeline, and it does not include new features or changes.

Update June 14, 2021: Microsoft is once again pushing another update for devices enrolled in the Dev Channel. This time the company is releasing build 21390.2025 as the update KB5004123 only to test its servicing pipeline.

About the author

Mauro Huculak is a Windows How-To Expert who started Pureinfotech in 2010 as an independent online publication. He has also been a Windows Central contributor for nearly a decade. Mauro has over 15 years of experience writing comprehensive guides and creating professional videos about Windows and software, including Android and Linux. Before becoming a technology writer, he was an IT administrator for seven years. In total, Mauro has over 21 years of combined experience in technology. Throughout his career, he achieved different professional certifications from Microsoft (MSCA), Cisco (CCNP), VMware (VCP), and CompTIA (A+ and Network+), and he has been recognized as a Microsoft MVP for many years. You can follow him on X (Twitter), YouTube, LinkedIn and About.me. Email him at [email protected].