error while upgrating Ubuntu from one version to higher

[Andy]

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

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: update-manager 1:0.156.14.17
ProcVersionSignature: Ubuntu 3.13.0-33.58~precise1-generic 3.13.11.4
Uname: Linux 3.13.0-33-generic x86_64
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: amd64
Date: Tue Aug 12 22:39:14 2014
EcryptfsInUse: Yes
GsettingsChanges:
 com.ubuntu.update-manager first-run false
 com.ubuntu.update-manager launch-time 1407868875
 com.ubuntu.update-manager window-height 536
 com.ubuntu.update-manager window-width 600
InstallationMedia: Ubuntu OEM 12.04 "UALinux" - Release amd64 (20130915)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: update-manager
Symptom: ubuntu-release-upgrader-core
UpgradeStatus: Upgraded to precise on 2014-08-12 (0 days ago)
VarLogDistupgradeTermlog:

[Andy (arooff)]

help

[Seth Arnold (seth-arnold)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. We appreciate the difficulties you are facing, but this appears to be a "regular" (non-security) bug. I have unmarked it as a security issue since this bug does not show evidence of allowing attackers to cross privilege boundaries nor directly cause loss of data/privacy. Please feel free to report any other bugs you may find.