What do you mean by isn't lock.. cause the light and evrything opens on my floppy disk but when i put something for it to be read, it says that its not format, cannot read the disk. When I try to format my floppy disk a prompt appears and says your disk can't be format!
first I'm going to assume that you are using 3.5" 1.44M floppies, hold it up so you can see the two openings, one of them has a slider, if it is closed(no light) it's locked, BTW, if these floppies were removed from the drive before the light went off, they make great frisbies
Number 13 is correct . Unfortunately most disks sold by retailers are locked as he said hold it up to a light you have to see light from only one of the square openings open. Move the slider on the back of the disk; the one thats locked and you will be able to format. If that doesnt work try a NEW FLOPPY Good Luck