do-release-upgrade

[BojanNS]

Checking package manager
Reading package lists... Done
Building dependency tree
Reading state information... Done
Building data structures... Done

Calculating the changes

Calculating the changes

Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

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 ubuntu-release-upgrader-core' in a terminal.

Restoring original system state

Aborting
Reading package lists... Done
Building dependency tree
Reading state information... Done
Building data structures... Done

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: update-manager 1:0.156.14.11
ProcVersionSignature: Ubuntu 3.11.0-15.25~precise1-generic 3.11.10
Uname: Linux 3.11.0-15-generic i686
NonfreeKernelModules: wl
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: i386
Date: Fri Apr 18 14:18:18 2014
GsettingsChanges:

InstallationMedia: Ubuntu 12.04.4 LTS "Precise Pangolin" - Release i386 (20140204)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: update-manager
Symptom: ubuntu-release-upgrader-core
UpgradeStatus: Upgraded to precise on 2014-04-18 (0 days ago)