I use a mac so may be different, but after I formatted my usb I had first added all the files into the the os folder and it didnt work, I went back deleted everything from the os folder and copied and pasted the 1 kaos file inserted it and it immediately worked. Not sure but I would just make sure there is just the one file in the os folder
Yep I tried every combination you could think of, I am a computer savvy person so I believe I followed all best practices.... What worked for me was switching from that particular PC to my MAC. I may try it again on a different PC I have just to debug when I get the time, maybe next time I upgrade and I will report back.