If your computer has an issue booting up, it is most likely an issue with the hard drive. To fix this problem simply buy a Windows rescue DVD for the Windows version your computer uses. These rescue DVDs can be bought for less than $5 at any store that sells electronics or at online stores such as Amazon or eBay. Once you have purchased the rescue DVD place it in the disk drive of your computer and turn it on. Then carefully read and follow the instructions on screen. If the rescue DVD does not fix the issue or your computer still won't boot, then the next step is to replace your hard drive. If you need assistance replacing your hard drive then feel free to check out our trouble shooting guide for the Toshiba Satellite A665-S5170 hard drive replacement.