BT4 Pre Final: Restore Grub after REinstalling Vista/7

Boot using BT4 DVD (Text Mode is sufficient)

mkdir /mnt/bt4

mount /dev/sda3 /mnt/bt4/
assuming 'dev/sda3' is your root partition

required if you have separate partition for boot:
mount /dev/sda1 /mnt/bt4/boot
assuming '/dev/sda1' is your boot partition

mount -t proc proc /mnt/bt4/proc/

mount -o bind /dev /mnt/bt4/dev/

chroot /mnt/bt4/ /bin/bash

grub
find /grub/stage1
root (hd0,0) where '(hd0,0)' is result from previous command
setup (hd0)
quit

reboot