could not calculate the upgrade

[James Parker]

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.

ProblemType: Bug
DistroRelease: Ubuntu 13.10
Package: ubuntu-release-upgrader-core 1:0.205.6
ProcVersionSignature: Ubuntu 3.11.0-26.45-generic 3.11.10.12
Uname: Linux 3.11.0-26-generic x86_64
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: amd64
CrashDB: ubuntu
Date: Thu Sep 4 15:55:24 2014
InstallationDate: Installed on 2014-04-09 (148 days ago)
InstallationMedia: Ubuntu 13.10 "Saucy Salamander" - Release amd64 (20131016.1)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
Symptom: ubuntu-release-upgrader
UpgradeStatus: Upgraded to saucy on 2014-09-04 (0 days ago)
VarLogDistupgradeTermlog: