Hi, I've a Dell Optiplex 390 with Win10 installed. Yesterday I added a new HDD and I installed WinXP on to it. Now Windows XP boot fine, but if I try to boot from the Win10 HDD, it fails and instead boots WinXP HDD. I've tried to repair the Windows 10 through a Win10 Installation USB key, both automatic repair and bootrec commands, but seems that it doesn't find any Windows installation. How can I do?