How to Boot a Computer from a CD

Two Methods: Booting a PC  Booting Mac OS X

Sometimes you need to boot from a CD in order to fix or upgrade your computer. The problem is, most computers are set to boot from the hard disk, without trying to boot from a CD. Getting your computer to do this can be convoluted, so follow these steps to make sure that you boot correctly.

Method 1 of 2: Booting a PC

1. Insert the disk. 
The disk must be bootable CD or DVD such as your Windows installation disk or a diagnostic disk.

2. Reboot your computer. Before you can boot from a CD or DVD, you need to make sure that the CD/DVD drive is set as the primary boot device.

• When you see the manufacturer’s logo, hit the key displayed to enter the BIOS setup menu. The key varies by manufacturer. The most common keys are F2, F10, F12, and Del. The key you need to hit will be displayed underneath the logo, or on the side of the screen.

• Once you are in the BIOS menu, select the Boot submenu. All manufacturers use slightly different BIOS layouts, so look for a variation on the name Boot.

• In the Boot menu, use the arrow keys to highlight the first device and change it to the CD/DVD player. Each BIOS menu will have a different way of displaying your drive. Some will list it by manufacturer, some label it Optical Drive, and others will simply say CD/DVD.

• Once your CD/DVD drive is set as the primary boot device, save your changes and exit. This will restart the computer

3. Boot from the CD.  Once the manufacturer’s logo disappears, you most likely will be prompted to press any key to boot from CD. Some bootable CDs will start automatically.

Method 2 of 2: Booting Mac OS X

1. Insert the disk. The disk must be a bootable CD or DVD, such as your Mac OS X installation DVD. Reboot or turn on your computer.


2. Hold down the C or Option key. After you hear the boot chime, hold down either the Option or the C key, depending on what you would like to do. The Option key will take you to a menu that allows you to select what device you would like to boot from, including the CD/DVD drive. The C key will skip this menu and automatically select the CD/DVD drive as the boot device.

• You may have to hold the key for a few moments. Wait for the menu to appear or for the boot sequence to start.

• Booting from CD is slower than booting from the hard drive, so don’t be alarmed if things appear to be loading slowly.

Sources and Citations

• http://www.macyourself.com/2011/04/24/boot-your-mac-from-cd-dvd-external-drive-or-usb-flash-drive/