To start installation, you should have Windows XP installation CD with its product key available. You have to buy a new Windows XP CD if you are not having that CD or you can not make contact with your computer company from whom you purchase a computer. You may need a boot CD or boot disk, but it is totally depend on which installation method you select. To install or upgrade to Windows XP by some techniques you should have Windows XP CD or boot disks. Evaluate the techniques to find out what media you will require. If the installation technique that you select requires you to switch on your PC from the Windows XP CD, your CD or DVD drive must be organized for this. For information about how to organize your PC to start from the CD or DVD drive, see the documentation that is integrated with your PC or contact the computer company.