I just downloaded the 64-bit Windows 10 ISO, and trying to create a pendrive installer (since my computer doesn't have an optical drive). The system I have available is Ubuntu 14.04, which is the same machine I'm trying to install Windows 10 to.
I tried every method listed in an Ask Ubuntu question, however the result is consistent: the drive is formatted properly, all files including the
bootx64.efi file are correctly located, but it is not possible to boot to the USB stick.
When I restart the computer, press F8 during POST to select where to boot and pick the USB, the screen just flashes and goes back to the normal GRUB screen.
Context: I have a dual boot of Win7 + Ubuntu installed to different HDDs. The USB stick is a generic, 8GB USB 2.0.
Specs: AMD FX-6300, ASUS M5A97, 8GB RAM, a 500GB HDD (Win7) and a 1TB HDD (2 partitions, 300GB Ubuntu, 700 generic/shared with Windows)