How to reinstall GRUB

[bizzard]

Many of those who use dual booting systems with Windows and Linux must have come across GRUB error. Its easy to reinstall GRUB if you have a bootable GRUB floppy.
Here is how to reinstall grub in a Debian system.

1. Creating GRUB floppy: It will be better to have a GRUB floppy everytime with you. To create one, after loading Linux, insert a floppy in drive and type
   grub-floppy /dev/fd0
2. Installing GRUB: Configure system to boot first from floppy and insert the GRUB floppy.
   In the grub> prompt, type the following commands.
   grub> root (hd0, x)
   here x refers to your Linux installed partition. You can find it by pressing the TAB key after root (hd0,
   grub> kernel /boot/vmlinuz <Kernel Version> root=/dev/hda<x+1>
   Kernel version is automatically detected by pressing TAB key after typing grub> kernel /boot/vmlinuz If the value of x in the previous step was 2, you must type 3 in the place of x+1
   
   grub> initrd /boot/initrd <Kernel Version>
   grub> boot
   
3. Now, you will be able to boot to the pre installed Linux in your system. After logging in as root, type the following in root terminal.
   
   grub-install /dev/hda

After this, you will be able to access the Linux installed in your system from the boot menu

[Doomed]

Also, you may be able to reinstall grub of the disk your distro came on, I know Suse is able to repair grub.

On a side note, for those who have come across a grub error, because linux has died and they want to boot into windows, you can still boot into windows by entering (hd0 is the drive you've got windows on and this time the x is the windows partition)

grub> root (hd0, x)

grub> chainloader +1
grub> boot

and that's it, the computer should boot into windows.

[bizzard]

grub> root (hd0, x)

grub> chainloader +1
grub> boot

yeah, the above command do work. But, for a permanent solution, you have to reinstall the GRUB boot loader. If you want only to access windows, with the Windows XP installation CD, choose the repair option and type the command "fixmbr". It will reinstall the boot configuration.