Photo wont show on usb on other machines?

Can someone plz help solve a printing problem. trying to get a photo printed on the asda machines,. have tried 2 USB sticks and a CD aswell as jpeg and .bmp formats, the photo is not in a folder. asda machine keeps saying theres no photo in the device. the machine definitely works cos the asda guy put his own usb in it to check it.copied pic to phone -didnt work. every photo on phone worked except the one we want. its definitely jpeg.. asda said they only do jpeg. tried saving the photo direct from facebook onto desktop then copying to the usb. tried taking a screenshot of the photo and saving as jpeg. nothing works. even the bloke at asda is baffled. everytime we try something the machine says theres no photo in the device but when we try the usb in other laptops or at other more expensive printing shops it works. Amy help to solve this problem would be really appreciated thanks