Failed to update ubuntu desktop with update manager

[Blair Chasteen]

I ran sudo apt-get upgrade like I normally do and there was a few packages still left to upgrade
The following packages have been kept back:
  compiz compiz-core compiz-dev compiz-gnome compiz-plugins compiz-plugins-default libcompizconfig0 libdecoration0 libdecoration0-dev libnux-2.0-0 libnux-2.0-common mc
0 upgraded, 0 newly installed, 0 to remove and 12 not upgraded.

so I ran update manager then it gave me the unknown error cannot install ubuntu-desktop.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: update-manager 1:0.156.7
ProcVersionSignature: Ubuntu 3.2.0-18.28-generic-pae 3.2.9
Uname: Linux 3.2.0-18-generic-pae i686
NonfreeKernelModules: fglrx
ApportVersion: 1.94.1-0ubuntu2
Aptdaemon:

Architecture: i386
Date: Mon Mar 12 18:03:07 2012
GsettingsChanges:
 com.ubuntu.update-manager first-run false
 com.ubuntu.update-manager launch-time 1331593331
 com.ubuntu.update-manager window-height 600
 com.ubuntu.update-manager window-width 600
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release i386 (20110427.1)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=
 TERM=xterm
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: update-manager
UpgradeStatus: Upgraded to precise on 2012-03-12 (0 days ago)