i called microsoft, and they said that E 68 with one red flashing light means your hard drive is screwed up. Your 360 will work fine, but when u plug your hard drive in it wont work and youll get the E 68 error message. Call XBOX customer support, and they'll tell you to send it to them and they'll repair it for free. In the meanwhile, buy a memory card and keep playing. Your game saves and other stuff will be lost though.