>> However, try to take a different USB stick, put the image back on and try
>> again. Some sticks just don’t behave.

Hello,

I might be stating the obvious, but I haven’t seen this in the discussion. I apologize in advance if thos has already been thought of.

I’m not sure how you created the usb stick, but the image doesn’t like being part of a multi boot setup. It has to own the stick. It can’t be in a subfolder, etc. I had this problem in the past when I used tools like yumi or rufus to create the install. I use dd on my linux machines. I forget what I used to create the stick on windows. I stopped using Windows regularly 4 or 5 years ago. Since I work fir myself, these days, I don’t need to. :-)

dd=input.iso of=<path to usb stick block device>

Cheers,
Curtis