Given only this detail I would not be able to offer much advice. We know that the stock Windows will bluescreen when booted from USB so your post means that it's not Windows as that would not be in use from a pen drive.
Try telling what OS, PC and what you think lead to this issue.
My computer when boots shows a blue screen. The Os is not being loaded. I tried to boot the computer from pen drive and CD Drive, un plugging the HDD, but the same error was repeating. Can anyone help me to sort the problem