From DailyTech: With Windows 10's release looming ahead on July 29, Microsoft Corp. (MSFT) has answered most questions about the highly anticipated (mostly) free operating system upgrade. But one unanswered question has been what fate will await those with Windows XP and Vista.
The official party line from Microsoft is that you will have to buy an individual license, or an OEM license resold in bulk. But for those with a Windows XP or Vista machine who don't want to spend $100 USD or more, it appears there's a clever workaround -- but only if you act immediately.
The workaround begins with a Windows 10 Insider Preview ISO.
Ordinarily, you can't install Windows 10 on a Windows XP or Windows Vista PC. But since at least Insider Preview Build 10130, consumer available ISOs have been offered direct from Microsoft. Once burned to a DVD, these ISOs can offer a clean install.
Does Microsoft officially approve of this loophole? Obviously not. Technically speaking these clean installs are not intended for Windows XP or Vista computers as that would arguably be bad or wrong. You're supposed to upgrade to Windows 7, 8, or 8.1 and then install the Preview Build.
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