I Can't See The Hard Drives

Are you sure they're hidden? In My Computer, try the Tools menu then Folder Options and click eth View tab. Tick to "Show hidden files and folder" and untick "Hide protected system files and folders", click Apply and OK your way out. If that doesn't help, look in Control Panel>Administrative Tools>Computer Management>Disk Management and see how many disks show up in the list.
 
Hidden hard drive? Uhmmm .. okay first power off the computer. Now turn it on but when you see the text on the screen go into the BIOS menu. Work your way with the menus to the Hard Drives. Do you see the hard drives listed? Write them down, and is that all of them? If one is not showing A) it is unplugged B) it is DEAD. Now reboot into Windows, Click the ORB in the bottom right, right click on COMPUTER and select MANAGE. Now go to Device Manager, and Disk Drives. Does that list show the same ones you wrote down? Yes / No?
If you see them, then click on Disk Management, scroll down the list in the bottom pane, do you see the drive that is 'missing' listed there? If you do but it shows it is unallocated, it needs to be FORMATED to be used. If it was 'working before' but unallocated now, the drive died and you lost everything on it.