could not calculate the upgrade plugin

[Justin Prim]

I get this pop up after it tells me that third party stuff has been turned off and while its in the Setting New Software channels area during the 15.04 distribution upgrade

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 3.16.0-36.48-generic 3.16.7-ckt9
Uname: Linux 3.16.0-36-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.7-0ubuntu8.4
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Sun Apr 26 11:43:18 2015
InstallationDate: Installed on 2014-11-15 (161 days ago)
InstallationMedia: Ubuntu 14.04.1 LTS "Trusty Tahr" - Release amd64 (20140722.2)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to utopic on 2015-04-26 (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.