Cannot upgrade ubuntu from 14.04 LTS to 15.10 neither to 16.04 LTS

[marco]

I cannot upgrade ubuntu from 14.04 LTS to 15.10 neither to 16.04 LTS.

Everytime I get the following error message:

"Impossibile calcolare l'avanzamento

Si è verificato un problema irrisolvibile durante il calcolo
dell'avanzamento.

I motivi possono essere:
* L'avanzamento a una versione di pre-rilascio di Ubuntu
* L'esecuzione dell'attuale versione di pre-rilascio di Ubuntu
* Pacchetti software non ufficiali non forniti da Ubuntu

Se non vengono installati, segnalare il problema usando il comando
«ubuntu-bug ubuntu-release-upgrader-core» in un terminale. "

"That for the English version stands for:

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 14.04
Package: ubuntu-release-upgrader-core 1:0.220.8
ProcVersionSignature: Ubuntu 3.13.0-88.135-generic 3.13.11-ckt39
Uname: Linux 3.13.0-88-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.21
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Sun Jun 19 22:56:49 2016
InstallationDate: Installed on 2012-03-25 (1547 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to trusty on 2016-06-20 (0 days ago)
mtime.conffile..etc.update.manager.release.upgrades: 2016-06-19T21:14:43.760286

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Hi marco. Could you please translate the Italian(?) into English? Maybe leave the original since that was the system's output, but if we could have a translation too that would be helpful. I don't want to seem intolerant of foreign languages, but as a bug triager I have to request a translation because English is the most commonly used language by developers and bug triagers. Thank you!

[Ads20000 (ads20000)]

This shouldn't happen and I have no idea what's causing the bug. But if you're still on Ubuntu 14.04 and haven't upgraded using a live USB/DVD, could you please try running `sudo do-release-upgrade` and `sudo do-release-upgrade -d` in Terminal and advise as to the results? Don't use the `-d` flag if you're on 16.04, because that will upgrade you to Ubuntu Yakkety (the development release), but sometimes it helps if you use that when trying to upgrade to 16.04.

If that works, then hopefully the logs you've got in the bug report there will be enough for the developers to fix the original bug.

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Before trying the commands above, you should remove any third-party or PPA packages from your computer. Go to Software & Updates -> Other Software to find what PPAs you have installed. Then use `sudo apt install ppa-purge ; sudo ppa-purge ppa_name` (replacing 'ppa_name' with the relevant PPA, typing in multiple PPAs separated by spaces if necessary). Then perhaps run `sudo apt update ; sudo apt upgrade` to ensure everything is fully up-to-date. You're also going to have to manually remove any software you've installed from DEB packages that aren't from the repositories. Use `sudo apt package_name` (replacing 'package_name' with the name of the package) to remove these manually (yes, you'll have to remember which packages you've installed manually).

After you've done all this, first try upgrading using the Software Update program (as you were trying originally). If that still doesn't work, try the commands I suggested in comment 3.