Upgrade from 14.04 LTS to 16.04 LTS failing

[Arunas]

The upgrade fails. The initial install was performed for kodibuntu.

System info:
Operating system Ubuntu Linux 14.04
Kernel and CPU Linux 3.13.0-24-generic on x86_64
Processor information AMD A6-6400K APU with Radeon(tm) HD Graphics , 2 cores

Failing with no real message:

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.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubuntu-release-upgrader-core 1:0.220.8
ProcVersionSignature: Ubuntu 3.13.0-24.46-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
NonfreeKernelModules: zfs zunicode zcommon znvpair zavl
ApportVersion: 2.14.1-0ubuntu3.21
Architecture: amd64
CrashDB: ubuntu
Date: Mon Aug 8 23:52:44 2016
InstallationDate: Installed on 2014-05-06 (826 days ago)
InstallationMedia: Ubuntu "Trusty" - Build amd64 LIVE Binary 20140504-15:29
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to trusty on 2016-08-09 (0 days ago)

[Brian Murray (brian-murray)]

Reviewing the files from your upgrade attempt you seem to have enabled a PPA that provides Xorg packages. This will prevent the upgrade as that PPA contains package version numbers greater than the release to which you are upgrading. You can revert the PPA by installing the ppa-purge package from the official Ubuntu archive and then running 'sudo ppa-purge oibaf'. After that you try upgrading and again and if it still fails open a new bug report. Thanks and good luck!