[Bug 1573103] [NEW] my lubuntu cannot upgrade from 14.04 to 16.04, want to know why?

[George]

Public bug reported:

Hi, there: 
I install blender from zip but not from apt source. is this the cause that I cannot upgrade the system?

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubuntu-release-upgrader-core 1:0.220.8
ProcVersionSignature: Ubuntu 3.19.0-58.64~14.04.1-generic 3.19.8-ckt16
Uname: Linux 3.19.0-58-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.19
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: LXDE
Date: Thu Apr 21 23:20:22 2016
InstallationDate: Installed on 2015-12-25 (118 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to trusty on 2016-04-21 (0 days ago)
VarLogDistupgradeTermlog:

** Affects: ubuntu-release-upgrader (Ubuntu)
     Importance: Undecided
         Status: New


** Tags: amd64 apport-bug dist-upgrade third-party-packages trusty

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to ubuntu-release-upgrader in
Ubuntu.
https://bugs.launchpad.net/bugs/1573103

Title:
  my lubuntu cannot upgrade from 14.04 to 16.04, want to know why?

Status in ubuntu-release-upgrader package in Ubuntu:
  New

Bug description:
  Hi, there: 
  I install blender from zip but not from apt source. is this the cause that I cannot upgrade the system?

  ProblemType: Bug
  DistroRelease: Ubuntu 14.04
  Package: ubuntu-release-upgrader-core 1:0.220.8
  ProcVersionSignature: Ubuntu 3.19.0-58.64~14.04.1-generic 3.19.8-ckt16
  Uname: Linux 3.19.0-58-generic x86_64
  ApportVersion: 2.14.1-0ubuntu3.19
  Architecture: amd64
  CrashDB: ubuntu
  CurrentDesktop: LXDE
  Date: Thu Apr 21 23:20:22 2016
  InstallationDate: Installed on 2015-12-25 (118 days ago)
  InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
  PackageArchitecture: all
  SourcePackage: ubuntu-release-upgrader
  UpgradeStatus: Upgraded to trusty on 2016-04-21 (0 days ago)
  VarLogDistupgradeTermlog:

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1573103/+subscriptions