hello i have a big problem, suddenly my mac froze so i force shut down and when rebooting instead of the apple sign a folder with a question mark keeps blinking with no response, so what shall i do?!!!! does it need a format?!!! i have stuff on my ilife that i didnt back up yet....is there any way that i can access the hard drive or somethin to back up my data?!!!!!! i have time machine but last time i updated it was a month ago!!! pls help!!