USB 3 Issue with EUFI installation

[SteveSi]

Windows 8/10 contain native USB 3.0 drivers. I don't think WinToUSB adds any. Try Win8. If both fail then maybe your hardware is not supported (did you have to install special USB 3 driver when installing Windows onto internal HDD?). if only Win 10 fails, then maybe MS have not added in all USB 3 drivers yet?