I bought New toshiba laptop with windows 8 which was working fine till one day a problem happen when turn on says theres an error that occur and it must restart then it goes right to black screen and back to the toshiba logo but with the preparing automatic repair underneath but it just goes black screen afterwards and just stays on the black screen.
try to reprogram it.. or reformat.. maybe there's a problem in its Operating System (like windows 7, windows 8, windows XP, linux ) . but try to bring it to those computer centers which offers diagnostic service for laptop.
Mine is doing the same exact thing. Did you find the problem. I have a USB recovery media & tried that. Had me back to original system but wasn't working right. Then back to this black screen again & preparing automatic repair.