Gabriel Aul, who is one of Microsoft's main spokespeople on Twitter, took to the social network to reveal that Windows 10 RTM will be free to Insider Preview users.
RTM (release to manufacturing) refers to the stage where Windows 10 is considered ready for mass distribution – the latest (and eighth) iteration is Build 10074, widely considered to be what is traditionally known as the beta version.
Microsoft already confirmed that Windows 10 will be free for Windows 7 and Windows 8.1 users, so in theory, a Windows Vista user could install the current Windows 10 Preview and upgrade to the final version when it is launched later this year.
What Aul hasn't said, though, is how Microsoft plans to limit and control the number of installs and how the licenses are transferred/managed post-installation.
(ed: Aul subsequently confirmed on Twitter that only those with a genuine, valid Windows 8.1 or Windows 7 license would be able to get Windows 10 for free).
What would, for example, prevent someone from downloading Windows 10 on 10 different, antiquated PCs, and then transfer those (or worse, illegally sell them) to a third-party down the line?
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Désiré has been musing and writing about technology during a career spanning four decades. He dabbled in website builders and web hosting when DHTML and frames were in vogue and started narrating about the impact of technology on society just before the start of the Y2K hysteria at the turn of the last millennium.