Well, to be honest, I've had the same stupid little problem. My situation, was my PC was essentially trying to boot from the USB stick. Even my Sony PSP, if it was causing it. Go to your BIOS and find your boot priority. Make SURE that your harddrive your current operating system is first boot priority, then CD drive (Incase you need to work on something without Windows) and if possible, and you know you wont use it, disable anything in your boot priorities regarding USB stuff, its not common to use USB things to boot with, check it out and lemme know how it went!