1. Boot by CDROM

2. Select Rescue Mode [F5]

3. Auto-detect and mount the HDD root filesystem at /mnt/sysimage

4. Check the filesystem once more at the single-user prompt

    # fsck -y /mnt/sysimage

5. Change the root directory to the HDD root filesystem

    # chroot /mnt/sysimage

6. Make sure that the GRUB (boot loader) configuration file is correctly set

    # vi /boot/grub/grub.conf

7. Re-install GRUB

    # grub-install options

5.0   Rescue Mode

#boot=/dev/hda1
default=0
timeout=10
splashimage=(hd0,0)/grub/splash.xpm.gz

# section to load linux
title Red Hat Linux (2.4.18-5.47)
        root (hd0,0)
        kernel /vmlinuz-2.4.18-5.47 ro root=/dev/hda2
        initrd /initrd-2.4.18-5.47.img

# section to load Windows XP
title Windows XP
        rootnoverify (hd0,0)
        chainloader +1