The upgrade from Windows 7 and 8.1 to Windows 10 will be free the first year. It won't be free in 2017! It's still unclear if you get an upgrade license or a f

The upgrade from Windows 7 and 8.1 to Windows 10 will be free the first year. It won't be free in 2017! It's still unclear if you get an upgrade license or a full license of Windows 10. The first one would mean, if you ever need to reinstall the PC/Notebook (harddisk/ssd crash), you would have to install Win7/8 and then upgrade to Win10 again (if the key allows that and is still valid in e.g. 2017). ReactOS is an attempt that building an open source version of Windows XP/7. It uses source code from WINE and it aims for better compatibility with legacy apps by using a WinNT-like OS-Kernel: http://www.reactos.org http://www.reactos.org