[ubuntu-uk] Help gnome 3 broke my laptop!

[Avi Greenbury]

Pete wrote:

> I was playing around trying to install gnome 3 onto my Ubuntu 11.04 
> system, this was done via synaptic, since then I have been given the 
> choice of 'gnome classic, KDE (plasma workspace), Arios (my original 
> system based on Ubuntu), recovery console, unity 2d, user defined 
> session' at login but none of them are my original desktop session
> and most give the error 'unable to load session' with the option to
> logout.

This is because everything Gnome 2 based has been upgraded to Gnome
3, including software libraries and configuration files. 

> I have 'completely removed' gnome 3 in synaptic but it only removed 1 
> package not the 139 it installed when I installed it!

Most desktop environments are installed with a 'metapackage', which is
simply an empty package that depends upon all the components of the
desktop environment - not just 'Gnome' but also, say, the gnome
configuration panel, and a mail client, and an IM client and the like.

When you installed that package, it depended upon 139 others, so they
were all pulled in, too. When you uninstalled it, the dependencies
weren't automatically removed; the default behaviour is to not remove
things it's not been asked to remove.

> 1/ most important how do I recover my original desktop session?

The only sure way that I know of is to reinstall. Your configuration
was clobbered by the Gnome 3 configuration on upgrade, so even were you
to sort the softwary bits out, you'd still be configuring
essentially from scratch.

> 2/ why did it install the KDE desktop environment without me even
> trying? 

That's hard to tell without knowing *exactly* what you did to upgrade
to Gnome3. Which repository did you use, which commands did you run,
etc?

> 3/ is there a way of listing the packages installed on a
> certain date/time to ensure I can manually remove them with the hope
> of restoring my system to it's previous state?

You can mess around with /var/log/dpkg.log to get that data, but bear
in mind that 'unpacking' is both part of initial install, and upgrade.

> thanks in advance (and no I will not be trying to install extra
> desktops on an existing system again, I will dual boot in future!!)

Everything in the standard Ubuntu repositories (that is, main, universe
and multiverse) will work fine. Conflicts can occur when you use PPAs
and other additional repositories - they're in PPAs and other
repositories precisely because they conflict with someting in the
standard repositories.

Other desktop environments should be fine, but running two different
major versions of the same program (as you did with Gnome) is always a
recipe for problems.


-- 
Avi