I am trying to spread the word about Linux in general and Ubuntu in particular. I made a Lubuntu Live USB for a friend for whom I spend a lot of time helping him with his Windows. He is not very knowledgeable and it took a while to get him able to boot the USB. After he finally got it working, he liked it, for a few days, but then it stopped working. After the word Lubuntu appears with the moving dots below, the screen goes blank and nothing else happens, although the USB stick is still working (the light is still on in the stick). The computer has to be manually powered down.

The USB is Lubuntu 13.10 desktop i386 and he used it on am HP Pavillion 500-205t. The USB did have Casper and I had installed GIMP and a card game. Unfortunately I cannot get any further info from my friend, but I do have the stick back and it does not work for me either (another stick created on the same day still does). I can look at all the files and folders on the stick, but would not know what to look for, any thoughts?