Insert the Windows 7 installation disc into the CD/DVD drive
Restart your computer.
If you see a prompt, press any key to boot from the CD. If you cannot start the computer from the CD, you may need to change the BIOS settings of your computer to do so. For more information, see "How to get your computer started from the CD."
Choose your language settings, and then click Next.
Click Repair your computer.
Select the operating system that you want to repair, and then click Next.
In the System Recovery Options window, click Startup Repair.
