upgrade to 11.04 fails

[Solitaire]

Trying to run the Distribution upgrade from 10.10 to 11.04 (attached log files)

I've removed all PPA's and uninstalled all programs associated
I've also ran "computer Janitor" to remove any non-official programs
Removed Nvidia proprietary driver

I keep getting the following error:

Could not determine the upgrade

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 against the 'update-manager' package and include the files in /var/log/dist-upgrade/ in the bug report

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: update-manager 1:0.142.23.1
ProcVersionSignature: Ubuntu 2.6.35-32.65-generic-pae 2.6.35.14
Uname: Linux 2.6.35-32-generic-pae i686
Architecture: i386
Date: Sat Jan 28 22:25:56 2012
InstallationMedia: Ubuntu 10.10 "Maverick Meerkat" - Release i386 (20101007)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: update-manager

[RedSingularity (redsingularity)]

What is the output of:

apt-cache policy upstart-job
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[Launchpad Janitor (janitor)]

[Expired for update-manager (Ubuntu) because there has been no activity for 60 days.]