I have windows XP and Scintific linux on same machine, both were working properly but due to some region I reinstalled window. now grub loader is not working and my system loading window. How can I install GRUB ?

Is Scientific Linux on a "live CD"? If so, you can install GRUB from there.

See the "booting" link below.

hi friend,

Insert the linux first disk in cdroom and enter to the rescue mode, either type linus rescue , or enter F5, It would direct to the shell script type
chroot /mnt/sysimage
then grub-install /dev/hda
then check grub vi /etc/grub.conf
Thank you

Hi -

Herre's a good link on Grub that might be helpful (might be somwhere between sumit dash's somewhat brief summary and pixellany's perhaps intimidating link):

http://josephhall.org/grub_install_hda1.html#reinstall

Good luck!

WARNING!
These instructions work on virtually all flavors of Windows 9x, NT and XP. But they do NOT necessarily work for Vista. Vista has a new - and very different - boot loader!

Hmmmm...It's all relative.......I wrote that because I had found other docs to be intimidating (confusing, incomplete--pick one)

hi dear,
Did u get the answer,or still u do have any problem if so plz write ur problem more elborately.

THANKS TO ALL THE ANSWERS........appreciate it. LINUX is mind boggling ( have a small mind), learning. Hacked the Windows bootloader and got it working. I know, I know, I use Windows VISTA, please be kind.

not sure if I am doing this correctly, any reply is most appreciated. I had windows XP, loaded Vista to double boot, mother board bye bye, new motherboard, reboot, VISTA ran OK, Windows XP bye bye (dual boot or "older version of windows" did not boot). So I loaded Suse Linux 64 version to see if it would find WinXP however it now only sees VISTA 64, is there anyway I can tell LINUX GRUB to boot into WinXP32?...(I do have the NT loader backed up), I am also an amateur in LINUX but I like it so far....looking at the best LINUX 64 bit version to load up as well. Thanks for the time so far
Qrazydutch (with a Q so as not to get the real crazies upset)

hello,
my dear friend please write your problem more elaborately i will be happy to help u sorting out your problem.

Moved to Linux-General

Prior to Vista you couldn't. When you installed (dual-boot) a later version of Windoze, it "upgraded" the ntldr to use the later release. From that later release is where the (Windoze) dual-booting is handled - by boot.ini. With Vista it's now handled by BCD.

So ... in theory you should be able to chainload directly to the XP partition from grub.
I haven't tried it - obviously ...

A XP or a Vista cannot be change from motherboard to motherboard.

M$ controls its OS by keeping a record of the hardware. Every hardware change scores points and when the total number of points exceeds a prefixed threshold the OS will lock up itself. It is M$'s way to stop the OS migrating from PC to PC. OEM version of the M$ system is supposed to die with the PC and cannot be migrated.

I believe a re-installation is needed and the user needs to talk to M$ to re-activate the OS too.

If it's just the motherboard you can get away with it - note that Vista works.
I've also changed motherboard on XP successfully. Second time (couple of hard disks, CD burner as well) it complained, and needed re-registration, but it did at least boot up.
Such are the woes of living in a bad lightning zone - even (home) UPS's don't always protect you.

So I can't explain why Vista works, and XP doesn't.
Maybe try fixing the BCD data.

Edit: thinking about this, saikee makes a good point about OEM. When I re-registered, I was quizzed specifically as to whether this was a OEM version.
I got the impression they weren't about to give me a new key if it was.