New
#30
@Fafhrd, Kari is a real "Stickler" for such details(legal activation).
If it was otherwise(using the VHD) he wouldn't even have posted about it, as he knows it would have been misused.
See this tutorial from him: Hyper-V - Native Boot VHD - Windows 10 Forums
It includes a tip to get a legal copy of Windows(insider preview) to be able to run SxS(side by side) with your original activated version:
TipIf you are not a Windows Insider but would like to test the latest Windows Insider build to help you decide if opting in to Insider builds would be something for you, you can do it even if you have never had or used Hyper-V or would not even like to set it up.
You can download free 90 day trial Hyper-V Windows 10 virtual machines from Microsoft, both the latest official release (build 10586 when writing this) and latest Insider build (14366).
See this thread for download instructions: Windows 10 virtual machines now available on Microsoft Edge Dev - Windows 10 Forums
You don't have to setup any virtualization software, nor do you need install anything, instead when you have downloaded the vm, mount the VHD it contains as told above and you can dualboot to your chosen Windows 10 build for 90 days, for free :)