Recently I got a new laptop, and I want to move the windows license from my previous laptop. The windows installed on my old laptop is the retail version of windows 8.1 and upgraded to windows 10. Is it possible to move the license? Or I need to purchase another license for the new laptop?
With the Windows 10 Anniversary update, it is possible to link and transfer a license using a Microsoft account. To check if your license is linked to your account, just open up the settings, check under "Update and Security" > "Activation". Once your license is linked, you should be able to log in on the other computer after windows has been installed, and then use the same menu to move your license to the new installation.
This is more made for desktop users who change motherboards, but I would suspect that this also works for going from one laptop to the other. Just keep in mind that this will deactivate the old installation
This page should help you through the process: http://www.windowscentral.com/how-re-activate-windows-10-after-hardware-change