Hello,
For some reason my pc won't load my Hitachi DeskStar hard drive. The windows just doesn't start and when I try to boot the cd to reinstall them a message appears that says "boot failure, please insert system disk and press enter". The cd is not corrupted because it works on other PCs. Also I tried to connect another hard drive to my pc and it was working fine. Although the other one connects with master and mine does with ATA. Can anyone help me, please?

It sounds like your hard drive crashed. To boot from cd, either find and press the boot menu key after powering on (look for it on the boot splash screen, mine is f12, some are f8 or esc) and select the cdrom or alter the bios boot order to boot from the cd before the hard disk (usually press f1 to get into the bios right when powering on). Might as well use the boot menu key (f12, f8, or esc when powering on).