Microsoft today began testing features for the future versions of Windows 10. The company is already finalizing the upcoming Windows 10 20H2 through its Beta Channel. However, today's build arrived for the Dev Channel (aka the Fast ring) with features that may end up in versions 21H1 and 21H2 scheduled for next year.

While the Windows maker has said that it won't be tying these builds to any specific versions, considering 20H2 is already done, these builds will likely be part of the two Windows 10 2021 feature updates. Just hours after the release of the build for the Insiders, the company has now also released the first ever Windows 10 ISO files from this development branch.

Hey #WindowsInsiders we also released the ISO for Build 20150 today as well! https://t.co/fbbsZPkmZN ^BLB

— Windows Insider (@windowsinsider) June 17, 2020

How to download Windows 10 ISO files for build 20150

Windows 10 2021 Build 20150 ISO files are now available todownload from the Windows Insider site.To be able to download these Windows 10 ISO files, you will first need to follow these steps to get yourself enrolled in the Windows Insider Program. [Windows Insiders can directly download the Windows 10 Build 20150 ISO files]

Sign up for the Windows Insider Program (click here).Make sure your machine meets the system requirements.Click here to download the ISO files.

As noted above, the company is also testing the Fall 2020 or 20H2 builds through the Beta Channel aka the Slow ring. This would be a minor update, which means Windows 10 May 2021 Update is expected to bring some major new features. If you are planning to test these builds that may make up version 21H1, you can now clean install using these ISO files.

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