bob <bob-barth@comcast.net> writes:

> I wrote GRUB to my MBR (by mistake). GRUB was not correctly configured.
>
> I get a GRUB prompt and I am stuck when dual boot to XP; Gentoo
> choice is OK.
>
> What to I do to fix my MBR?

I agree with the other posters that installing grub to the MBR is
the best way -- I always do it that way.

In your /boot/grub/grub.conf you need to add some lines like this:
title Windows
root (hd0,0)
chainloader +1

The correct value for 'root' will depend on where your WinXP is
installed. I happen to have an old-style FAT32 partition at
(hd0,0) because I multiboot several versions of Windows and that
is the easiest way to do it. But your WinXP may be installed on
a different partition, I don't know.

You can learn a lot about how grub works by using its interactive
interpreter mode: when the grub prompt appears just hit 'c' for
(c)ommand-line interpreter and then type 'root' and hit the TAB
key for a list of all the partitions. In general if you don't
know what to type next just hit TAB and grub will show you a list
of choices. It's really great once you know how to do it.