can't do-release-upgrade

[Patrizio Bruno]

Impossibile calcolare l'avanzamento

An unresolvable problem occurred while calculating the upgrade:
E:Error, pkgProblemResolver::Resolve generated breaks, this may be
caused by held packages.

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

Se nessuna delle precedenti è la causa, segnalare questo problema
tramite il comando «ubuntu-bug update-manager» da terminale.

Ripristino dello stato originale del sistema

Interruzione
Reading package lists... Done
Building dependency tree
Reading state information... Done
Building data structures... Done
=== Command detached from window (Tue Oct 18 15:50:21 2011) ===
=== Command terminated with exit status 1 (Tue Oct 18 15:50:21 2011) ===

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: update-manager 1:0.150.3
ProcVersionSignature: Ubuntu 2.6.38-11.50-server 2.6.38.8
Uname: Linux 2.6.38-11-server x86_64
NonfreeKernelModules: nvidia
Architecture: amd64
Date: Tue Oct 18 15:46:35 2011
DpkgHistoryLog.txt:

DpkgTerminalLog.txt:

GConfNonDefault: /apps/update-manager/check_new_release_ignore=
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=it_IT:en
 PATH=(custom, no user)
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
SourcePackage: update-manager
UpgradeStatus: Upgraded to natty on 2011-10-18 (0 days ago)

[Walter Garcia-Fontes (walter-garcia)]

Thanks for taking the time to report this bug and helping to make Ubuntu better. Could you please add the log files from '/var/log/dist-upgrade/' to this bug report as separate attachments? Thanks in advance.

[sim909 (srizzi)]

Could this be a duplicate of Bug #873883 ?