Try to upgrade to xenial with a sudo do-release-upgrade -d

[abeman]

No more details. The upgrade doesn't work at all :/

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubuntu-release-upgrader-core 1:0.220.8
ProcVersionSignature: Ubuntu 3.16.0-49.65~14.04.1-generic 3.16.7-ckt15
Uname: Linux 3.16.0-49-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu3.19
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: MATE
Date: Sat Apr 2 23:51:00 2016
InstallationDate: Installed on 2015-07-02 (275 days ago)
InstallationMedia: Ubuntu 14.04.2 LTS "Trusty Tahr" - Release amd64 (20150218.1)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to trusty on 2016-04-02 (0 days ago)

[Brian Murray (brian-murray)]

I think the upgrade fails to be calculated due to this:

Investigating (5) libgtk-3-0 [ amd64 ] < 3.10.8-0ubuntu1.6 -> 3.18.9-1ubuntu3 > ( libs )
Broken libgtk-3-0:amd64 Dépend on libwayland-egl1-mesa [ amd64 ] < none -> 11.1.2-1ubuntu2 > ( libs ) (>= 10.0.2)
  Considering libwayland-egl1-mesa:amd64 -1 as a solution to libgtk-3-0:amd64 214
  MarkKeep libgtk-3-0 [ amd64 ] < 3.10.8-0ubuntu1.6 -> 3.18.9-1ubuntu3 > ( libs ) FU=0
  Holding Back libgtk-3-0:amd64 rather than change libwayland-egl1-mesa:amd64
Broken libgtk-3-0:amd64 Dépend on libwayland-egl1 [ amd64 ] < none > ( none )
  Considering libwayland-egl1-mesa-lts-utopic:amd64 8 as a solution to libgtk-3-0:amd64 214
  Added libwayland-egl1-mesa-lts-utopic:amd64 to the remove list
  Fixing libgtk-3-0:amd64 via keep of libwayland-egl1-mesa-lts-utopic:amd64
  MarkKeep libwayland-egl1-mesa-lts-utopic [ amd64 ] < 10.3.2-0ubuntu1~trusty2 > ( libs ) FU=0

Maybe if you switch to mesa-lts-vivid or mesa-lts-wily things will work out better.

[Petrus Adamus (dohnp5a1)]

Well, any recommendation for an amateur what to do?

[abeman (stiven-guillaume)]

Hello. Thank you for the answer.
I'm ok to switch to mesa-lts-vivid, but for that i have to remove all this package :

L'information suivante devrait vous aider à résoudre la situation :

Les paquets suivants contiennent des dépendances non satisfaites :
 libegl1-mesa-lts-vivid : Dépend: libgbm1-lts-vivid (>= 7.11~1) mais ne sera pas installé
                          Dépend: libgl1-mesa-dri-lts-vivid (= 10.5.9-2ubuntu1~trusty2) mais ne sera pas installé
E: Impossible de corriger les problèmes, des paquets défectueux sont en mode « garder en l'état ».

And synaptic seems OK to install it but need to remove package like xorg or ubuntu-desktop...

[Launchpad Janitor (janitor)]

[Expired for ubuntu-release-upgrader (Ubuntu) because there has been no activity for 60 days.]