I had triple booted RHL 8 with Win XP and Win2K3.  Had grub as boot loader but had to reinstall Win2K3.  So the boot loader got overwritten and now only win gets booted. Can I recover by old boot loader by any means or have to do a fresh install??

I also have knoppix 3.1..if it can help in any way..but it doesn't give any option to install the boot loader. Or could the linux Cd install the boot loader? OR any 3rd party stuff out there?

A fresh install is way over the top...

Boot off the floppy disk you made during installation of Redhat (you did make one right?!?) and once in run the command:
# grub-install /dev/hda

So you haven't got that floppy disk eh? When booting from the redhat CD does it give you an option to boot a pre-installed system? Or possibly rescue? Failing that, boot off the knoppix CD, mount your root partition somewhere (eg /mnt/temp), change your root to this (chroot /mnt/temp) and then run the grub-install command.

Once you are in and got it all working, do yourself a favour and make a boot floppy with the mkbootdisk command, test it and keep it in a safe place in case you need it again.

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