my fd asked me to reformat his computer, but he didint wanna delete all his stuff, so i brought my hard-drive, plug it in to his computer as the secondard hard-drive. i copied all the stuff to my hard-drive which he didnt want to delete, took out my hard-drive, den reformat his computer.........when it was done, i plug my hard-drive again to his computer, put all his stuff back to his computer.....den took out n brought it home.....but when i plug it in back to my computer, turn on my computer, sometimes it showed something about reboot with a work device or reboot with the device's media cd etc with a black screen....sometimes it showed the screen says everything works but the windows didnt start sucessful, choose safe mode or normally start windows or last worked conj. etc.....i tried every one....the normally start windows n last good conj. could load to the loading windows screen (which is theres a "windwos" in the middle and theres a line under "windows" n loading one) but after loading....it reboot my computer auto. other safe modes reboots my computer after loading too, but it loaded in black screen....
wat should i do now??
wat should i do now??