Comment 24 for bug 180619

William, I hope you've used a package management tool other than the new GUI-based system upgrade utility, otherwise this is going to feel like being taught how to run butterfly time trials when you don't know how to swim yet... i.e., you need to know how to drive 'aptitude' in a terminal window.

1) Add this line back into the file /etc/apt/sources.list

deb http://us.archive.ubuntu.com/ubuntu/ gutsy main restricted universe multiverse

2) Then run 'apt-get update', to refresh your sources. (NOTE: If you are not root, you will need to prepend all commands with 'sudo', that is, 'sudo apt-get update'.) Next, _save your Xorg config_. Copy /etc/X11/xorg.conf to your home directory or someplace safe.

3) Run 'aptitude' in a command-line window, preferably a console window (i.e., hit CTRL-ALT-F1). Don't have it? Then 'apt-get install aptitude' first.

(Aside: Before anybody piles on me for not using 'synaptic', this can be a bit tricky because we're going to be playing with X11 packages here. Synaptics is a GUI that runs in X11... won't be able to do that if it's broken, so you _will_ need to know how to do this from command-line.)

4) Look at the package list. Type "/". In the search box, type "^xserver-xorg$". Hit return. You should now have a list of stuff starting with _xserver-xorg_, with the top one selected. Hit v. Move down one line and select the version "1:7.2-5ubuntu13". Hit + and then q.

5) Move down one line to xerver-xorg-core. Hit v. Select 2:1.3.0.0.dfsg-12ubuntu8. Hit +. Hit q. Notice now that there are 43 (or more) BROKEN packages. You have to fix these by downgrading them.

6) Hit b to go to the first broken package. Hit v to see the versions. In most cases, there's only one other choice. Select the other version and hit +. If the red capital B goes away, then you're good. If not, pick another older version till the B goes away. Hit q to get out. Rinse and repeat for all the broken packages.

7) Hit g (twice) to go get the older packages and install them. Will take a while.

8) Hopefully you didn't have any install errors. At this point you need to restart X. This is where you really really want to be on the console, so CTRL+ALT+F1 now if you didn't already. In that window, login and type 'sudo /etc/init.d/gdm stop' (I assume you're using Gnome.) This will stop the Gnome display manager and also stop all X instances. Type 'ps axf | grep X' to make sure they are all dead. Then, restart gdm... 'sudo /etc/init.d/gdm start'. You should get your login prompt back (if it was working under Hardy, then it should work again under Gutsy bits...) Login to X.

8a) If the screen flickers a couple times then gives you an error screen, then something is wrong and you need to fix something in your X config, possibly install or reinstall a driver or something (I could only guess... there are a lot of things that could go wrong). CTRL+ALT+F1 to get back to your console. Then look at the file /var/log/Xorg.0.log. Look for EE for clues...

9) If the last step (8) work well, then you should now be able to connect via VNC again without it crashing.

10) If you want, fire back up 'aptitude' and go back in and mark all those packages as "held" by hitting = on each one. It's pretty easy to find out which ones by hitting g, you'll get a list of packages it wants to upgrade. Unfortunately, that doesn't stop the GUI upgrade tool from noticing they are held, so it doesn't actually do much good unless you continue to only use aptitude to manage packages.

Hope that helps.