I'm trying to upgrade from 11.04 to 11.10, but get this error:
An unresolvable problem occurred while calculating the upgrade: E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.
This can be caused by: * Upgrading to a pre-release version of Ubuntu * Running the current pre-release version of Ubuntu * Unofficial software packages not provided by Ubuntu
If none of this applies, then please report this bug using the command 'ubuntu-bug update-manager' in a terminal.
To attempt to fix this, I disabled all software sources not provided by Ubuntu, and I uninstalled all software not provided by Ubuntu in the Ubuntu Software Center. Synaptic tells me I still have natty/restricted nvidia-current, nvidia-glx-180, and nvidia-glx-185 installed. Could these last packages be what is holding back the upgrade? I hesitate to uninstall them because I'm worried that doing so may significantly reduce my screen resolution. What can I do to find out what packages are holding back the upgrade?
sudo apt-get remove libglib2-ruby1.8
fixed the problem and allowed the upgrade to complete successfully.