Here’s an excerpt of the Microsoft blog post where the company states that Windows 10 will “remain activated” for Insiders – even if they clean install Windows 10:
“As long as you are running an Insider Preview build and connected with the MSA you used to register, you will receive the Windows 10 final release build and remain activated. Once you have successfully installed this build and activated, you will also be able to clean install on that PC from final media if you want to start over fresh.”
Now, Microsoft has updated its announcement blog post quietly and removed some important phrases from the blog post. Here’s the same excerpt from the updated blog post:
"As long as you are running an Insider Preview build and connected with the MSA you used to register, you will receive the Windows 10 final release build. Once you have successfully installed this build, you will also be able to clean install on that PC from final media if you want to start over fresh. It’s important to note that only people running Genuine Windows 7 or Windows 8.1 can upgrade to Windows 10 as part of the free upgrade offer."
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