did you install any programs or updates recently
the easiest way to fix is to borrow a windows disk of someone if your laptop didnt come with one and do a repair install
you will have to give us more info on what you did before this started to happen
i was playing a game and it said my harddrive have problems or something else i forgot what it said, but it said something had a problem and i googld how to fix it , it told me to run chkdsk utility , so i ran it and it took hours, like 1 hour later , the scaning thing was only at like 50% or something. My power went off at like 60% and i tried to restart my computer, but it keeps restarting by itself over and over again.
So there is no way i can fix it without a CD?