impossible to upgrade fron xubuntu 14.10 to xubuntu 15.04

[Diego Xavier]

When i am using the update manager to upgrade mi xubuntu 14.10 it shows me an error message and is not continuing with the upgrade. There is no explanation, because i have updated and upgrated my xubuntu before upgrading to the next version (15.04)

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: ubuntu-release-upgrader-core 1:14.10.10
Uname: Linux 4.0.0-040000-generic x86_64
ApportVersion: 2.14.7-0ubuntu8.4
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: XFCE
Date: Thu Apr 23 14:57:27 2015
InstallationDate: Installed on 2014-11-16 (158 days ago)
InstallationMedia: It
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.