I installed (or better: I began the installation... ) Linux one month ago and now I love it. So yesterday night I used Partition Magic to hardly reduce Windows space and increase the space for Linux. But... horror, when rebooting GRUB no longer works !!!
I have a GRUB promt and no GUI screen.
I tried reinstalling GRUB from CD, both on MBR and on first boot partition sector, I tried installing LILO, but the result is the same.: the GRUB prompt...
I have a boot floppy for Linux so I can access to my system this way, but this is not a solution, of course...
PLEASE, HELP ME: I don't want to reinstall the whole Linux !!! Let me know how to make my grub work again, PLEASE !!!!

P.S.: Be patient : I know this is an old problem and there is a lot of stuff in the forum about it, but in this moment I'm very panicked and I need someone helping me...
Thanks in advance.

Grub can't find its files, Reinstall Grub on the MBR

su to root
This should reinstall grub. make sure your root (hdx,x) points at your boot partition which contains the grub folder.

I want to be sure:

1- I have to install grub in the MBR even if I've Windows XP installed? (I read it's better to install in the first sector of /boot partition in this case).

2- Be patient (as I said I'm a panicked ) : I have to install grub again from RedHat CD or can I do this from the terminal? By typing what (grub-install? )? Or the commands you 've written before are already the installation procedure?

Thanks

The Partition magic program always screws up grub or lilo, and I would caution you against using it. You can always use the fdisk and mk*** commands under Linux. Still there is no use crying over spilled milk.

Just boot the system using your boot floppy, then log in as root and follow the commands that leonscape said, and I guess you will be out of the woods.

Yes, probably you are right about crying over spilled milk.

But what does it mean the 'root (hdx,x)' command ? What's the second item: Assuming my boot partition is hd5 I should enter
root (hd5,5) ?

Hoping not to bore you again...

hd5? your missing a letter, after the hd bit. Since grub count from zero not 1, 5 becomes 4.

(hdx, 4)

So if its,
a = 0
b = 1
c = 2
d = 3

my /boot partition is on hda5 so mine would be root(hd0, 4).

Thanks to all !!!!
Now everything is like before... no, something changed: I have less confiance in Win related software and more in Linux... and in Linux people too !!!

Thanks again !

Glad its all working

And if you have any more problems, we are here to help you again.