Evo N200

The BIOS, which handles the initial start up of your computer, cannot find your hard drive and thus cannot boot your operating system (ie, Windows). Open up your computer and confirm the power cable is firmly connected to the hard drive and that the cable that connects the hard drive to the motherboard is firmly secure.

If both of these check out, then try downloading this bootable CD on another computer. This CD, among other things, has a few hard drive utilities that will help further diagnose the problem.

http://www.ultimatebootcd.com/

Finally, if the utilities on this CD are unable to see the hard drive itself, then is may need to be replaced. Try testing with another hard drive or another cable to connect it to the motherboard.