Unable to upgrade from Utopic to Vivid

[Nick Jones]

Using the Software Updater to upgrade from Utopic to Vivid, after fetching the files I get the error message:

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 14.10
Package: ubuntu-release-upgrader-core 1:14.10.10
ProcVersionSignature: Ubuntu 3.16.0-34.47-generic 3.16.7-ckt8
Uname: Linux 3.16.0-34-generic x86_64
ApportVersion: 2.14.7-0ubuntu8.4
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Thu Apr 23 10:52:22 2015
InstallationDate: Installed on 2014-11-21 (153 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release amd64 (20141022.1)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to utopic on 2015-04-23 (0 days ago)
VarLogDistupgradeTermlog:

[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 different versions of packages essential to Ubuntu. The page, https://launchpad.net/~xorg-edgers/+archive/ppa, contains details on to how to revert to the official Xorg packages for the xorg-edgers PPA. Instructions for reverting to official Xorg packages should be similar for the PPA that you have enabled.

[Nick Jones (nick-10goto10)]

Yep thanks for your time - purging the ppa for xorg packages allowed the upgrade to go ahead.