i have Toshiba Satellite A105-S4014 laptop, and two days ago it stopped working. After the initial Toshiba screen, another screen comes up saying: "Windows could not start because the following file is missing or corrupt: \WINDOWS\system32\config\SYSTEM You can attempt to repair this file by starting Windows Setup using the original Setup CD-ROM. Select 'r' at the first screen to start repair." I have a lot of important stuff, and i really do no want to reformat it. Please help, asap.