Repairing Ubuntu without loosing data or breaking Windows

[NoOp]

On 01/20/2011 04:49 AM, Enrique Becerra wrote:
> Hi people
> Is there any guide I can follow to repair my Ubuntu installation
> without loosing important Ubuntu data or breaking Windows XP
> installation?
> 
> My PC has a dual boot (Ubuntu 10.10 / Windows XP) but Ubuntu is not
> working because it freezes when gdm shows and can't run in safemode
> from any grub entry. I have my CD ready to begin, but I get "scared"
> when I reach the point where it asks me partition stuff... will it
> format everything again, right?
>

I think what Zenwiz is attempting to advise is to try an in-place
reinstall from the liveCD. Note: *before* attempting to do this, back up
any critical data files that you have in your home folders. You can use
the liveCD to do this. This is from my notes of doing an in-place
reinstall from 9.04, but you should be able to do the same with 10.10
without much effort. If you'd prefer to wait, I'll replicate on a 10.10
tomorrow or the next day & update the instructions:

Boot to the liveCD and then select the run as normal option just to make
sure that all is working. Use the liveCD to save any data off of the
drive that is critical to you (taxes, photos, documents, etc). Open
gparted (System|Administration|Gparted) and make note of all of your
partitions. You can also open a terminal and:

$ sudo fdisk -l

In fact, it's a good idea if you do that & post the results back here
before you proceed further.

Unmount the drive and then select the install icon on the desktop.

When you get to the install part it will go something like this (this
was from one of my old Jaunty/9.04 notes, but lucid/10.04 /maverick
10.10 should be pretty much the same:

Where to you want to put Ubuntu 9.04?
o Install them side by side, choosing between them at each startup (by
default this is checked)
o Install using the entire disk
o Specify partitions manually (advanced)
  (select this last option)

Forward
I choose to 'Edit Partition' /dev/sda1 (*format unchecked*)
(You'll need to determine which is the correct /dev/sdaX on your system)
Use as: ext4
Format Partition: *UNCHECKED*
Mount Point: /
OK
Forward
I get the standard warning "The file system on /dev/sda1
assigned to / has not been marked for formating...".
Continue

That will perform an in-place reinstall of the system on the /dev/sdaX
you've selected without disturbing your /home and /opt folders.

That said, it might be better if you tell us exactly what what started
the problem to begin with & what you've done to troubleshoot so far. Try
booting to recovery mode and select the dpkg option to see if that will
correct the problem first. If it's a gdm problem, then quite often the
issue is an incorrect graphic driver; give us as much details about your
system as you can (model, graphic card, memory, monitory etc.) An easy
way to do this is to boot to the liveCD, ensure you have internet
working, and then in a terminal issue:

$ sudo lshw > myhardware.txt
$ gedit myhardware.txt

and then copy & paste the results here:
http://pastebin.ubuntu.com/
past it into the 'Content' box, then click the 'Past!' button. Post back
here on the resulting URL/link so that someone can take a look at your
hardware details.