This is a Draft coz I didn't proof it yet!!!
First of all when you successful boot with live CD
- open terminal
- type "sudo grub"
- find the location via command "find /boot/grub/stage1"
- then put it with "root (hd?,?)" // ? = result from 3.
- finally type "setup (hd0)"
Ref. http://ubuntuforums.org/showthread.php?t=224351