impossible to upgrade ubuntu from 17.04 to 17.10

[Michele Giacomelli]

after an 'apt dist-upgrade'
and an 'do-release-upgrade' i get this error:

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.

probably my problem is one of the 3 listed but there is no help to solve the problem...

many thanks,
  Michele

ProblemType: Bug
DistroRelease: Ubuntu 17.04
Package: ubuntu-release-upgrader-core 1:17.04.10
ProcVersionSignature: Ubuntu 4.10.0-37.41-generic 4.10.17
Uname: Linux 4.10.0-37-generic x86_64
NonfreeKernelModules: nvidia_uvm nvidia_drm nvidia_modeset nvidia
ApportVersion: 2.20.4-0ubuntu4.5
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: GNOME
Date: Wed Nov 1 16:36:36 2017
InstallationDate: Installed on 2017-07-03 (120 days ago)
InstallationMedia: Ubuntu 17.04 "Zesty Zapus" - Release amd64 (20170412)
PackageArchitecture: all
ProcEnviron:
 TERM=xterm-256color
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to zesty on 2017-11-01 (0 days ago)

[dino99 (9d9)]

That version is now dead
http://news.softpedia.com/news/ubuntu-17-04-zesty-zapus-has-reached-end-of-life-upgrade-to-ubuntu-17-10-now-519360.shtml

A fresh clean install is (by experience) more stable