Originally Posted by saptech
once you booted the LiveCD, just reinstall Grub to MBR.
Just an FYI: Since GRUB requires a lot more space than a 512 byte boot sector can provide, it must
have access to the files in the /boot directory. Most Linux distributions also allow GRUB to be installed on the VBR
of the Linux boot partition, which comes in handy if Windows overwrites the master boot record. By putting the GRUB 1st stage loader on the VBR, all that needs to be done to boot Linux is to mark the correct partition as active. That's a bit easier than reinstalling GRUB IME because I can use any disk utility to change the active partition.