I run kubuntu and have dual booted with win xp no problem until now. Suddenly it will
not give me the option of booting windows.If I select "other operating systems " I get

Error 11 -unrecognized device string.
Can I repair this fault with the boot loader.

Grateful for any help.

Have you changed anything since the last time it worked correctly?

Assuming that you can get into Kubuntu, please post the contents of /boot/grub/menu.lst

I have changed nothing and here is the file you requested.(thanks for the reply)

# menu.lst - See: grub(8), info grub, update-grub(8)
# grub-install(8), grub-floppy(8),
# grub-md5-crypt, /usr/share/doc/grub
# and /usr/share/doc/grub-doc/.

## default num
# Set the default entry to the entry number NUM. Numbering starts from 0, and
# the entry number 0 is the default if the command is not used.
#
# You can specify 'saved' instead of a number. In this case, the default entry
# is the entry saved with the command 'savedefault'.
# WARNING: If you are using dmraid do not use 'savedefault' or your
# array will desync and will not let you boot your system.
default 0

## timeout sec
# Set a timeout, in SEC seconds, before automatically booting the default entry
# (normally the first entry defined).
timeout 10

## hiddenmenu
# Hides the menu by default (press ESC to see the menu)
#hiddenmenu

# Pretty colours
#color cyan/blue white/blue

## password ['--md5'] passwd
# If used in the first section of a menu file, disable all interactive editing
# control (menu entry editor and command-line) and entries protected by the
# command 'lock'
# e.g. password topsecret
# password --md5 $1$gLhU0/$aW78kHK1QfV3P2b2znUoe/
# password topsecret

#
# examples
#
# title Windows 95/98/NT/2000
# root (hd0,0)
# makeactive
# chainloader +1
#
# title Linux
# root (hd0,1)
# kernel /vmlinuz root=/dev/hda2 ro
#

#
# Put static boot stanzas before and/or after AUTOMAGIC KERNEL LIST

### BEGIN AUTOMAGIC KERNELS LIST
## lines between the AUTOMAGIC KERNELS LIST markers will be modified
## by the debian update-grub script except for the default options below

## DO NOT UNCOMMENT THEM, Just edit them to your needs

## ## Start Default Options ##
## default kernel options
## default kernel options for automagic boot options
## If you want special options for specific kernels use kopt_x_y_z
## where x.y.z is kernel version. Minor versions can be omitted.
## e.g. kopt=root=/dev/hda1 ro
## kopt_2_6_8=root=/dev/hdc1 ro
## kopt_2_6_8_2_686=root=/dev/hdc2 ro
# kopt=root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro

## Setup crashdump menu entries
## e.g. crashdump=1
# crashdump=0

## default grub root device
## e.g. groot=(hd0,0)
# groot=(hd1,0)

## should update-grub create alternative automagic boot options
## e.g. alternative=true
## alternative=false
# alternative=true

## should update-grub lock alternative automagic boot options
## e.g. lockalternative=true
## lockalternative=false
# lockalternative=false

## additional options to use with the default boot option, but not with the
## alternatives
## e.g. defoptions=vga=791 resume=/dev/hda5
# defoptions=quiet splash

## should update-grub lock old automagic boot options
## e.g. lockold=false
## lockold=true
# lockold=false

## Xen hypervisor options to use with the default Xen boot option
# xenhopt=

## Xen Linux kernel options to use with the default Xen boot option
# xenkopt=console=tty0

## altoption boot targets option
## multiple altoptions lines are allowed
## e.g. altoptions=(extra menu suffix) extra boot options
## altoptions=(recovery) single
# altoptions=(recovery mode) single

## controls how many kernels should be put into the menu.lst
## only counts the first occurence of a kernel, not the
## alternative kernel options
## e.g. howmany=all
## howmany=7
# howmany=all

## should update-grub create memtest86 boot option
## e.g. memtest86=true
## memtest86=false
# memtest86=true

## should update-grub adjust the value of the default booted system
## can be true or false
# updatedefaultentry=false

## should update-grub add savedefault to the default options
## can be true or false
# savedefault=false

## ## End Default Options ##

title Ubuntu 8.04.1, kernel 2.6.24-21-generic
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-21-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro quiet splash
initrd /boot/initrd.img-2.6.24-21-generic
quiet

title Ubuntu 8.04.1, kernel 2.6.24-21-generic (recovery mode)
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-21-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro single
initrd /boot/initrd.img-2.6.24-21-generic

title Ubuntu 8.04.1, kernel 2.6.24-19-generic
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-19-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro quiet splash
initrd /boot/initrd.img-2.6.24-19-generic
quiet

title Ubuntu 8.04.1, kernel 2.6.24-19-generic (recovery mode)
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-19-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro single
initrd /boot/initrd.img-2.6.24-19-generic

title Ubuntu 8.04.1, kernel 2.6.24-18-generic
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-18-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro quiet splash
initrd /boot/initrd.img-2.6.24-18-generic
quiet

title Ubuntu 8.04.1, kernel 2.6.24-18-generic (recovery mode)
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-18-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro single
initrd /boot/initrd.img-2.6.24-18-generic

title Ubuntu 8.04.1, kernel 2.6.24-16-openvz
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-16-openvz root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro quiet splash
initrd /boot/initrd.img-2.6.24-16-openvz
quiet

title Ubuntu 8.04.1, kernel 2.6.24-16-openvz (recovery mode)
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-16-openvz root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro single
initrd /boot/initrd.img-2.6.24-16-openvz

title Ubuntu 8.04.1, kernel 2.6.24-16-generic
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-16-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro quiet splash
initrd /boot/initrd.img-2.6.24-16-generic
quiet

title Ubuntu 8.04.1, kernel 2.6.24-16-generic (recovery mode)
root (hd1,0)
kernel /boot/vmlinuz-2.6.24-16-generic root=UUID=60a4252f-cd5e-4fa7-bad0-6f0ef0874c1c ro single
initrd /boot/initrd.img-2.6.24-16-generic

title Ubuntu 8.04.1, memtest86+
root (hd1,0)
kernel /boot/memtest86+.bin
quiet

### END DEBIAN AUTOMAGIC KERNELS LIST

# This is a divider, added to separate the menu items below from the Debian
# ones.
title Other operating systems:
root


# This entry automatically added by the Debian installer for a non-linux OS
# on /dev/sda1
title Microsoft Windows XP Home Edition
root (hd0,0)
savedefault
makeactive
chainloader +1

Oooops---I should have suggested leaving out all the commented lines at the beginning.....

Here's the problem:
The lines in bold should simply be deleted. The entry for Windows appears to be OK---assuming that Windows is on the first partition of disk #1. (That's what (hd0,0) means in bash-ese.)

Also, I would delete some of the Ubuntu entries---unless you really use all those different kernels. (Make a backup first)

Mnay thanks you have cured my problem.I managed to edit the menu file
with sudo gedit and now all working fine.

Thanks again for the help it is very much appreciated.

Regards

Dave