upgrade aborted because of ppp, pptp-linux, network-manager-pptp

[Horea Aflat]

Please check the attached screen shot.
The bug happened at the end of installation at configurations.
It says: Errors were encountered while processing:
ppp
pptp-linux
network-manager-pptp
...
pppconfig
If you find a solution can you please email me.

Regards
Horea

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubuntu-release-upgrader-core 1:16.04.14
ProcVersionSignature: Ubuntu 3.19.0-65.73~14.04.1-generic 3.19.8-ckt22
Uname: Linux 3.19.0-65-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Thu Jul 28 21:09:57 2016
EcryptfsInUse: Yes
InstallationDate: Installed on 2015-08-28 (335 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
Symptom: ubuntu-release-upgrader
UpgradeStatus: Upgraded to xenial on 2016-07-29 (0 days ago)
VarLogDistupgradeAptclonesystemstate.tar.gz:
 Error: command ['pkexec', 'cat', '/var/log/dist-upgrade/apt-clone_system_state.tar.gz'] failed with exit code 127: polkit-agent-helper-1: error response to PolicyKit daemon: GDBus.Error:org.freedesktop.PolicyKit1.Error.Failed: No session for cookie
 Error executing command as another user: Not authorized

 This incident has been reported.
VarLogDistupgradeTermlog: