Either your disk is an illegal copy or your mainboard requires updated drivers to detect the CD due to copy protection.
If it is Call of Duty and you are running a Gigabyte 7N400Pro mainboard than it is the latter. Unless it is an illegal copy.
Or perhaps the disk is faulty. Or your CD lense has to be cleansed.
You even failed to mention the name of the game, that is very sloppy of you.