If there is anyone that can help me with this problem, that would be great! My macbook was working fine yesterday, however, my whole system completely froze up on me. I tried everything to close down all windows, but nothing worked. So, I just powered down the whole machine. I waited a few minutes before powering it up again, and that is when a new problem occured. The apple logo and start sound are shown/heard, but it sort of lags there for a few minutes and then just shuts down the whole machine. Does not get to login window. What should I do? Any help appreciated!