You have to mount the HD partition.
sudo mkdir /media/myntfs
sudo mount -r -t ntfs /dev/hda1 /media/myntfs
This will mount hda1 (the first partition on the first pata drive) on the directory /media/myntfs. If you a sata drive, you need to replace hda1 by sda1. If it's not the first HD, the 'a' has to change to something else ('b' for the second HD, 'c', etc). And if it's not the first partition, change the '1' to '2', '3' etc (whatever is applicable).
The first line is only required to create the mountpoint. Once the mountpoint exists, you don't have to do that step (after every boot of the liveCD you have to do this).
You can replace myntfs
by any name that you fancy (as long as it does not exist yet).
The commands start with sudo as you need root privileges.
PS you have to enter the commands in a terminal (applications>accesories>terminal)