how to multi boot my pc with xp, ubuntu & fedora.
initially i had xp & ubuntu in dual boot working smoothly..........
once installed fedora.........
all went upside down........
ie, i can see the foldes in ubuntu but none of the data could be accessed............

Could you provide more information on your Fedora & Ubuntu installation. Do you have separate home directories (for your regular user).

Your question isn't clear to me on whether you mean that you can't access files in the Ubuntu install when running Fedora, or whether when you boot up Ubuntu, you can't access your own files.
How are the partitions mounted?
What is the UID of your user in each distro?
What is the the primary GID of your user in each distro?
What are the permissions of your home directories in each distro?

initially it was a dual boot pc with xp & ubuntu
after installing fedora, i cannot login to ubuntu.
i can mount the partitions onto fedora only as ro mode..
it seems as if i should, edit my /bot/grub/menu.lst of fedora.
but i have no idea regarding the same.......

Quote:

how to multi boot my pc with xp, ubuntu & fedora. initially i had xp & ubuntu in dual boot working smoothly.......... once installed fedora......... all went upside down........

This should not give you any headache, Fedora can co-exist with Ubuntu and Xp peacefully. So long as you have installed Fedora in a separate partition everything should work alright. In this case, you did not even needed to install any boot loader for the latest fedora installation: you only need to add an entry into the /boot/grub/menu.lst pointing to fedora root, kernel, and initrd. Or is your Fedora using Grub2 ? That is another story. Get familiar with Grub bootloader, read from this page.

Quote:

ie, i can see the foldes in ubuntu but none of the data could be accessed............

We need to know more about how you allocate your disk partitions, and apportion your different folders. Where did your install fedora? what does "fdisk -l" command return? post it here.

Hope it helps.

Disk /dev/sda: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x454679a6

Device Boot Start End Blocks Id System
/dev/sda1 * 1 1275 10241406 7 HPFS/NTFS
/dev/sda2 1276 5127 30941190 f W95 Ext'd (LBA)
/dev/sda3 5128 6171 8385930 83 Linux
/dev/sda4 6172 6302 1052257+ 82 Linux swap / Solaris
/dev/sda5 1276 2550 10241406 7 HPFS/NTFS
/dev/sda6 2551 2672 979933+ 82 Linux swap / Solaris
/dev/sda7 2673 3668 8000338+ 83 Linux
/dev/sda8 3669 5127 11719386 83 Linux

If you are now able to boot Fedora and have mounted and can read your Ubuntu files, just navigate to the Ubuntu /boot/grub/menu.lst file and copy the first entry for Ubuntu to your Fedora /boot/grub/menu.lst file. I don't use Fedora so the file may be grub.conf instead of menu.lst. I believe one is a link to the other. You need to do this as root.

You can solve this simply by editing " grub.conf or /boot/grub/menu.lst."

Actually i had also faced the similar situation.
* My university gives us a laptop loaded with Windows XP
* Then i had installed openSUSE ( becoz i like it, most of edu work can be done in SUSE )
* After that i had installed ubuntu. ( becoz it is simpler )

MY suse has the beatiful penguin theme to select different OS's. But when i had installed ubuntu , this bootloader removed. I hate ubuntu bootloader, it is looklike command mode prompt. So i had followed this.....

* After logging into the SUSE i had repaired the Bootloader , so that primary bootloader is SUSE.
* then SUSE penguin theme comes to select OS's.
* Now when I select Ubuntu, ubuntu menu displays , i had removed this by editing ubuntu "/boot/grub/menu.lst." Since i don't want to uninstall grub of ubuntu. May be it will be required for future purposes. So I had just made select time to 0.

SO Now " only penguin theme of openSUSE grub comes for me".

check for the file grub.conf.
It may be present in

/etc/grub.conf
/boot/grub/grub.conf

check for
title Ubuntu
rootnoverify ( sda??????????????)
chainloader +1


??? = your ubuntu boot partition.

If you are able to modify, make a backup and then try. or else post the code in that file.

I am attaching the data's obtained after logging as root:

fdisk -l

Disk /dev/sda: 320.0 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x454679a6

Device Boot Start End Blocks Id System
/dev/sda1 * 1 1275 10241406 7 HPFS/NTFS
/dev/sda2 1276 5127 30941190 f W95 Ext'd (LBA)
/dev/sda3 5128 6171 8385930 83 Linux
/dev/sda4 6172 6302 1052257+ 82 Linux swap / Solaris
/dev/sda5 1276 2550 10241406 7 HPFS/NTFS
/dev/sda6 2551 2672 979933+ 82 Linux swap / Solaris
/dev/sda7 2673 3668 8000338+ 83 Linux
/dev/sda8 3669 5127 11719386 83 Linux

Out of this my the root of my ubuntu was /dev/sda7. I mounted it onto my /media/disk-4 and collected the contents of ubuntu /media/disk-4/boot/grub/menu.lst, it is as follows:

[root@localhost /]# cd /media/disk-4/boot/grub
[root@localhost grub]# cat menu.lst

# 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=aeb54d26-f3df-4479-9671-a4b8a0e59c4a ro

## default grub root device
## e.g. groot=(hd0,0)
# groot=aeb54d26-f3df-4479-9671-a4b8a0e59c4a

## 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

## specify if running in Xen domU or have grub detect automatically
## update-grub will ignore non-xen kernels when running in domU and vice versa
## e.g. indomU=detect
## indomU=true
## indomU=false
# indomU=detect

## 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 9.04, kernel 2.6.28-11-generic
uuid aeb54d26-f3df-4479-9671-a4b8a0e59c4a
kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=aeb54d26-f3df-4479-9671-a4b8a0e59c4a ro quiet splash
initrd /boot/initrd.img-2.6.28-11-generic
quiet

title Ubuntu 9.04, kernel 2.6.28-11-generic (recovery mode)
uuid aeb54d26-f3df-4479-9671-a4b8a0e59c4a
kernel /boot/vmlinuz-2.6.28-11-generic root=UUID=aeb54d26-f3df-4479-9671-a4b8a0e59c4a ro single
initrd /boot/initrd.img-2.6.28-11-generic

title Ubuntu 9.04, memtest86+
uuid aeb54d26-f3df-4479-9671-a4b8a0e59c4a
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 Professional
rootnoverify (hd0,0)
savedefault
makeactive
chainloader +1


Now i am attaching the contents of my fedora /boot/grub/menu.lst:
[root@localhost grub]# cd /boot/grub
[root@localhost grub]# cat menu.lst
# grub.conf generated by anaconda
#
# Note that you do not have to rerun grub after making changes to this file
# NOTICE: You do not have a /boot partition. This means that
# all kernel and initrd paths are relative to /, eg.
# root (hd0,2)
# kernel /boot/vmlinuz-version ro root=/dev/sda3
# initrd /boot/initrd-version.img
#boot=/dev/sda
default=0
timeout=5
splashimage=(hd0,2)/boot/grub/splash.xpm.gz
hiddenmenu
title Fedora (2.6.27.5-117.fc10.i686)
root (hd0,2)
kernel /boot/vmlinuz-2.6.27.5-117.fc10.i686 ro root=UUID=208e5da5-cbcb-4928-8fce-cf22fb27cd8e rhgb quiet
initrd /boot/initrd-2.6.27.5-117.fc10.i686.img
title Other
rootnoverify (hd0,0)
chainloader +1

Now what should i do next? How to edit my /boot/grub/menu.lst?

clearly saying, ubuntu is missing in your FEDORA grub.

it has default is fedora....
after 5 sec
it displayes fedora, and other ...may be XP

is n't it ??

In your fedora menu.lst make these modifications.

instead of

add this

I am not sure about this... make a backup... and then test it.

in case if it doesn't work wha tshould i do with the backup?
i have no idea?? how to come to the previous state?

hey....
i tried it..........
i could only see the listing on the grub loader.
the problem is error 13: incompatible executable format. as i press ubuntu option on the loader........
what to do next?

um...

you should just run
from your Fedora system

grub.conf is read-only and will be auto-edited
when using update-grub?

see if that works?

sorry it doesn't..........
now what i did is that i edited my grub loader as:-( This is with reference to my previous query.
experiment:1
------------
default=0
timeout=5
splashimage=(hd0,2)/boot/grub/splash.xpm.gz
hiddenmenu
title Fedora (2.6.27.5-117.fc10.i686)
root (hd0,2)
kernel /boot/vmlinuz-2.6.27.5-117.fc10.i686 ro root=UUID=208e5da5-cbcb-4928-8fce-cf22fb27cd8e rhgb quiet
initrd /boot/initrd-2.6.27.5-117.fc10.i686.img

title Ubuntu 9.04, kernel 2.6.28-11-generic
root (hd0,1)
kernel /dev/sda7/boot/vmlinuz-2.6.28-11-generic ro quiet splash
initrd /dev/sda7/boot/initrd.img-2.6.28-11-generic
chainloader +1

title Microsoft XP Professional
rootnoverify (hd0,0)
savedefault
makeactive
chainloader +1


Now what happens is that, my grubloader lists out the fedora,ubuntu and xp.
Out of this fedora and xp works on selecting.
But for ubuntu, it shows error 17: cannot loaded the specified partition when i edit the menu.lst as above.

experiment:2
------------
default=0
timeout=5
splashimage=(hd0,2)/boot/grub/splash.xpm.gz
hiddenmenu
title Fedora (2.6.27.5-117.fc10.i686)
root (hd0,2)
kernel /boot/vmlinuz-2.6.27.5-117.fc10.i686 ro root=UUID=208e5da5-cbcb-4928-8fce-cf22fb27cd8e rhgb quiet
initrd /boot/initrd-2.6.27.5-117.fc10.i686.img

title Ubuntu 9.04, kernel 2.6.28-11-generic
root (hd0,6)
kernel /dev/sda7/boot/vmlinuz-2.6.28-11-generic ro quiet splash
initrd /dev/sda7/boot/initrd.img-2.6.28-11-generic
chainloader +1

title Microsoft XP Professional
rootnoverify (hd0,0)
savedefault
makeactive
chainloader +1

But for ubuntu, it shows error 15: file not found. when i edit the menu.lst as above.

what to do next?
I am online.......
plz help me out????????