I've just created a multiboot USB stick using Yumi. I tried to start my notebook (Asus K70IO) using it, but all I see is just a black screen with blinking underscore even after waiting for minutes. If during this time I remove the USB stick I get the message: "Operating system load error".

How do I properly load my Yumi USB stick and use it? I've tried formatting it using Yumi's checkbox to format the stick in FAT32 too, but it didn't help.

Now I tried to use Sardu 2.0.5 and met same problem: black screen and blinkin underscore, if I remove stick I see "Operating system load error" and my OS starts to boot.

At the same time if I create bootable USB stick from ISO using UltraISO it boots smoothly.