Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

The title says it all... I'm having lots of issues after upgrading 9.04 to 9.10 - I want to reinstall without losing my files and I gave away my Ubuntu Disc and I can't make another one right now...

How can I force Ubuntu 9.10 to reinstall itself (without losing my information)?


The issues are: unresponsive mouse: [fixed by modding xorg.conf] and weird graphics issues which don't seem to be hardware or software, I can't tell. (specifically, bouncing lines on top of my screen and a loading bar on the shutdown screen - my friend says he has 9.10 and that the bar shouldn't be there.)


I ran sudo dpkg-reconfigure -phigh -a and it didn't work. The following is my terminal's output. Any ideas would be welcome.

moshe@moshe-laptop:~$ sudo sh
[sudo] password for moshe: 
# sudo dpkg-reconfigure -phigh -a
 * Disabling power management...                                         [ OK ] 
update-rc.d: warning: /etc/init.d/acpi-support missing LSB information
update-rc.d: see <>
 * Checking battery state...                                             [ OK ] 
acpid stop/waiting
acpid start/running, process 3544
 * Stopping web server apache2                                                  apache2: Could not reliably determine the server's fully qualified domain name, using for ServerName
 ... waiting                                                             [ OK ]
 * Starting web server apache2                                                  apache2: Could not reliably determine the server's fully qualified domain name, using for ServerName
                                                                         [ OK ]
Caching application data...
Generating mime/codec maps...
Caching application data...
Generating mime/codec maps...
 * Starting AppArmor profiles                                                   Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox-3.5
                                                                         [ OK ]
 * Reloading AppArmor profiles                                                  Skipping profile in /etc/apparmor.d/disable: usr.bin.firefox-3.5
                                                                         [ OK ]
dpkg-trigger: dpkg-trigger must be called from a maintainer script (or with a --by-package option)
share|improve this question
up vote 5 down vote accepted

To reinstall without losing your info ...

  1. Make a backup of the info you want to keep.
  2. Test the backup.
  3. Reinstall. Make sure the root partition gets reformatted, because you want to get rid of the old Ubuntu 9.04 stuff completely.
  4. Restore the backup.

You could attempt to perform the installation and try forcing the installer *not* to format the root partition, and that would keep the files you're probably interested in keeping. But it would leave files around from the previous install, it might lead to problems during the installation, and it might create problems later.

I don't know what you're considering "your information", but I'm assuming your user's HOME directory (or the entirety of /home) is the main candidate. If you have a website or database installed you'll also want to back those up (usually these are under /var).

And you probably want to make a backup of /etc as well, but don't automatically restore that one.

To reinstall without an install disc ...

Ubuntu provides many installation options; installing from the CD is only one of them. See the Installation page at the Community Ubuntu Documentation.

In particular, here is the section on Installation without a CD:

The documents listed below provide instructions for installing Ubuntu without using a CD or CD-ROM drive.

As you can see, there are lots of options. I think the best option might be to use a USB stick (Installation/FromUSBStick), if that's an option for you. If you still have the LiveCD ISO, or can download it again, and you have a spare USB stick you can use, this is a good option.

Installing from within a running Linux (Installation/FromLinux) might be an option for you, but it can be complicated -- in particular the debootstrap option (bottom of the page) is very powerful, but the process is not for the faint of heart.

Finally, one of the network installation options might work.

share|improve this answer
How does one reinstall without the disc, though? – Nathaniel Dec 24 '09 at 6:23
@Nathaniel: good point, i neglected to address that. will fix. – quack quixote Dec 24 '09 at 9:01
yes sure if you still have the ISO you can install usb-creator and make a boot USB to install without a disc – phunehehe Jan 4 '10 at 12:14
no longer relevant, but check for you since it was thorough. – Moshe Jan 6 '10 at 5:50

Agree with Quack's posting. One trick:

dpkg --get-selections > myselections

That stores all your installed packages in a file named "myselections".

After you install the new version:

dpkg --set-selections < myselections
aptitude install

should reinstall all the packages you had before.

Also, save the contents of /etc/ somewhere, that contains all your configuration info.

share|improve this answer

First you have to explain what the "issues" are. Are they system wide or local to your user account?

The first thing you could do is add a new user. Login with that user and see if the issues go away. If they do, the easiest thing to do would be to just move your documents/media to the new user account.

If the problems don't go away, then that is easy to fix as well.

What I would do is purge all non-standard software to get down to a bare bones install. this means removing all of X, gnome, etc.

#this will list all non crucial packages
aptitude search '~i (~poptional|~pextra)'
#this should remove them all. 
aptitude purge '~i (~poptional|~pextra)'

aptitude might flip out about removing that many packages at once so it might be easy to do them in chunks..

aptitude search '~i (~poptional|~pextra)' -F %p|xargs -n 20 echo aptitude purge > /tmp/
sh /tmp/

once everything is removed, do a

aptitude reinstall '~pstandard'
aptitude install ubuntu-desktop

that should get you a almost-like-new system.

Most of that is probably irrelevant though, since adding a new user account with fresh settings will probably fix any issues you are having.

share|improve this answer

sudo dpkg-reconfigure -phigh -a

share|improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .