problem upgrading to 15.04

[vanessa]

$ lsb_release -rd
Description: Ubuntu 14.04.3 LTS
Release: 14.04

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubuntu-release-upgrader-core 1:0.220.8
ProcVersionSignature: Ubuntu 3.16.0-30.40~14.04.1-generic 3.16.7-ckt3
Uname: Linux 3.16.0-30-generic x86_64
NonfreeKernelModules: nvidia zfs zunicode zcommon znvpair zavl
ApportVersion: 2.14.1-0ubuntu3.19
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: XFCE
Date: Sat Jan 23 19:21:31 2016
InstallationDate: Installed on 2014-05-25 (607 days ago)
InstallationMedia: Xubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.2)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to trusty on 2016-01-23 (0 days ago)
VarLogDistupgradeTermlog:

mtime.conffile..etc.update.manager.release.upgrades: 2016-01-23T18:41:14.305709

[Brian Murray (brian-murray)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. This particular bug has already been reported and is a duplicate of bug 1534374, so it is being marked as such. Please look at the other bug report to see if there is any missing information that you can provide, or to see if there is a workaround for the bug. Additionally, any further discussion regarding the bug should occur in the other report. Please continue to report any other bugs you may find.