Because, you didn't choose the CD drive like a bootable, or the CD disk is not bootable.
A CD-ROM drive is not needed to boot the computer. Just put the hard drive first in the boot order in the BIOS.
If you have a USB drive and your BIOS supports booting from a USB device then try that.
No, you normally do not need a CD to reboot the computer. Your operating system should be located on the hard drive. However, if you do not have a functioning hard drive with a working operating system, you may need to boot your computer from a CD boot disc.
Make sure the CD drive is the first boot device in the BIOS.
You need to change your BIOS boot settings to boot from CD/DVD not floppy.
Insert the CD with the operating system on it into your computer's disk drive. Now boot the computer and the machine should give you the option of booting from the CD.
A bootable CD has an operating sytem (usually a form of Linux or Windows) copied to the CD starting at track 0 on the CD. If your computer has a bios that defines one of your CD drives in the power on/restart boot sequence, you can boot your system from such a CD. Bootable CDs are used by developers/software companies to install Windows and Linux onto your computer's hard drive. Bootable CDs are also used by some anti-virus products to allow a "for sure" clean scan capability on a possibly infected system. Bootable CDs are activated by placing the CD in the CD drive, powering the computer down, a then powering the computer back on (cold boot). The power on boot usually follows a sequence of 1) check floppy drive for bootable disk, 2) check CD drive for bootable CD, and then 3) boot from designated hard drive.
Insert the windows XP Disc into the CD Drive, and reboot the computer. Boot from the CD. Then follow the instructions.
The computer wishes to boot a program from a portible device, E.G. Flash drive, CD/DVD etc.
If you formatted the drive that contained the main operating system you will need to boot off of a CD, DVD, floppy or USB drive that contains an operating system such as a system restore disk that came with the computer, a commercial operating system disk such as Windows XP or a free Linux 'Live CD' such as Ubuntu or openSUSE. If your computer is not recognizing the CD/DVD drive as a boot device you will need to add the CD/DVD drive as a boot device in your computer's BIOS. When you computer first turns on your will need to hit a specific key on your keyboard (a lot of times the 'delete' key) to enter 'setup' (aka the BIOS). Refer to the instructions for your particular BIOS to add the CD/DVD drive as a boot device (more info here http://www.hiren.info/pages/bios-boot-cdrom)
what it means is on startup of your computer the first thing your computer looks at is the CD ROM if there is no CD in the ROM drive it will then go to either floppy disc if you have one ,or read off your hard drive and windows should start up. all this info is put into your bios on the first time setup. Okay, I understand that but it will not boot … it stay at "CD-Rom Boot Priority .. No Medium Reboot and select proper boot drive" what do I select? 1…2…3…
if your first boot device is an optical drive, this allows you to boot from a recovery disk or live CD in case of hard drive failure or corruption. This can be useful for troubleshooting computer problems.