not able to upgrade from 12.04 to 14.04

[nikolareljin]

not able to upgrade from 12.04 to 14.04

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 12.04
Package: update-manager 1:0.156.14.17
ProcVersionSignature: Ubuntu 3.2.0-67.101-generic 3.2.60
Uname: Linux 3.2.0-67-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: amd64
Date: Tue Aug 12 21:04:04 2014
GsettingsChanges:
 com.ubuntu.update-manager first-run false
 com.ubuntu.update-manager launch-time 1407889473
 com.ubuntu.update-manager show-details true
 com.ubuntu.update-manager window-height 529
 com.ubuntu.update-manager window-width 1028
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release amd64 (20120823.1)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: update-manager
Symptom: ubuntu-release-upgrader-core
UpgradeStatus: Upgraded to precise on 2014-08-13 (0 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Lorne sunley (lornes)]

I removed the Samba4 beta from my machine and the upgrade could proceed

[Nicolas (nlasaigues)]

I don't have installed anything called like that.

[robin (robinp)]

when i run:
$ cat /var/log/dist-upgrade/20140912-2154/|grep Broken
i get this:
Broken xz-utils:i386 Conflicts on xz-lzma [ i386 ] < 5.1.1alpha+20110809-3 > ( utils )
Broken libmono-wcf3.0a-cil:i386 Conflicts on libmono-wcf3.0-cil [ i386 ] < 2.10.8.1-1ubuntu2.2 > ( cli-mono ) (< 3.2.3)
Broken libatk-adaptor:i386 Conflicts on at-spi [ i386 ] < 2.4.0-1ubuntu2 > ( misc )
Broken libsnmp-base:i386 Breaks on libsnmp15 [ i386 ] < 5.4.3~dfsg-2.4ubuntu1.2 > ( libs ) (< 5.7.2~dfsg-5)
Broken overlay-scrollbar-gtk2:i386 Conflicts on liboverlay-scrollbar-0.2-0 [ i386 ] < 0.2.16-0ubuntu1.1 > ( libs ) (< 0.2.16+r348)
Broken overlay-scrollbar-gtk3:i386 Conflicts on liboverlay-scrollbar3-0.2-0 [ i386 ] < 0.2.16-0ubuntu1.1 > ( libs ) (< 0.2.16+r348)
Broken osspd:i386 Conflicts on oss-compat [ i386 ] < 1 -> 6 > ( universe/sound )
Broken im-config:i386 Conflicts on im-switch [ i386 ] < 1.20ubuntu5.2 -> 1.23ubuntu1 > ( universe/x11 )
Broken libperl5.14:i386 Depends on perl-base [ i386 ] < 5.14.2-6ubuntu2.4 -> 5.18.2-2ubuntu1 > ( perl ) (= 5.14.2-6ubuntu2.4)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libpostproc-extra-52:i386 Conflicts on libpostproc52 [ i386 ] < none -> 6:0.git20120821-4 > ( universe/libs )
Broken libbamf3-0:i386 Depends on bamfdaemon [ i386 ] < 0.2.126-0ubuntu1 -> 0.5.1+14.04.20140409-0ubuntu1 > ( libs ) (= 0.2.126-0ubuntu1)
Broken libbamf0:i386 Depends on bamfdaemon [ i386 ] < 0.2.126-0ubuntu1 -> 0.5.1+14.04.20140409-0ubuntu1 > ( libs ) (= 0.2.126-0ubuntu1)
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-0 [ i386 ] < 1.10.6-1~precise1 -> 1.16.4-0ubuntu2 > ( libs ) (< 1.15)
Broken libclutter-1.0-0:i386 Breaks on libcogl9 [ i386 ] < 1.10.0-0ubuntu2 > ( libs )
Broken libcogl15:i386 Breaks on libclutter-1.0-...

[robin (robinp)]

removing the problem packages listed in my last comment allowed the upgrade to continue. some of them may have been local or obsolete packages originating from PPAs; i cannot tell as i do not have synaptic installed.