error processing archive /var/cache/apt/archives/gnome-session_3.11.4-0ubuntu1~trusty1_all.deb (--unpack)

[Elias Psallidas]

Using Ubuntu GNOME 14.04 LTS 64bit with the following PPAs included in the Software Sources:
1) gnome3
2) gnome3-staging
3) gnome3-next
I get the following error when executing 'sudo apt-get dist-upgrade':
========================
Preparing to unpack .../gnome-session_3.11.4-0ubuntu1~trusty1_all.deb ...
Unpacking gnome-session (3.11.4-0ubuntu1~trusty1) over (3.9.90-0ubuntu8) ...
dpkg: error processing archive /var/cache/apt/archives/gnome-session_3.11.4-0ubuntu1~trusty1_all.deb (--unpack):
 trying to overwrite '/usr/share/xsessions/ubuntu.desktop', which is also in package ubuntu-session 3.9.90-0ubuntu8
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Errors were encountered while processing:
 /var/cache/apt/archives/gnome-session_3.11.4-0ubuntu1~trusty1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
========================

My installations is two days old.
I've never seen the '(Broken pipe)' reference before, so I assume this is a packaging issue.

I don't know what information to provide, so I kindly ask for your understanding and guidance if more information is needed.
Attached to the report are the outputs of:
1) cat /etc/apt/sources.list
2) ls /etc/apt/sources.list.d
3) uname -a

And here is the full output of 'sudo apt-get dist-upgrade':
============================
elias@ubuntu:~$ sudo apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages will be REMOVED:
  ubuntu-session
The following NEW packages will be installed:
  geoclue-2.0 gnustep-base-common gnustep-base-runtime gnustep-common
  libgnustep-base1.24 libobjc4 unar
The following packages will be upgraded:
  empathy empathy-common file-roller gnome-session gnome-session-bin
  gnome-session-common mcp-account-manager-goa
7 upgraded, 7 newly installed, 1 to remove and 0 not upgraded.
Need to get 0 B/10.9 MB of archives.
After this operation, 27.3 MB of additional disk space will be used.
Do you want to continue? [Y/n] y
WARNING: The following packages cannot be authenticated!
  gnome-session gnome-session-bin gnome-session-common mcp-account-manager-goa
  empathy empathy-common geoclue-2.0 file-roller
Install these packages without verification? [y/N] y
(Reading database ... 348408 files and directories currently installed.)
Preparing to unpack .../gnome-session_3.11.4-0ubuntu1~trusty1_all.deb ...
Unpacking gnome-session (3.11.4-0ubuntu1~trusty1) over (3.9.90-0ubuntu8) ...
dpkg: error processing archive /var/cache/apt/archives/gnome-session_3.11.4-0ubuntu1~trusty1_all.deb (--unpack):
 trying to overwrite '/usr/share/xsessions/ubuntu.desktop', which is also in package ubuntu-session 3.9.90-0ubuntu8
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Errors were encountered while processing:
 /var/cache/apt/archives/gnome-session_3.11.4-0ubuntu1~trusty1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
=======================

Using 'apt-get install -f' and 'dpkg --configure -a' doesn't make any differnce.

Thank you in advance.

[Elias Psallidas (eliasps)]

Fixed - Invalid

[Tim Lunn (darkxst)]

Re-opening, this is due to ubuntu splitting ubuntu session out of gnome-session binary package, we need to rebase gnome-session in the ppa on the latest archive version.

[Elias Psallidas (eliasps)]

Hi Tim.

I filed this bug report because my system was (and is) barely customized when this error occured. Like I said, the 'Broken Pipe' thing made me believe that this was some kind of packaging issue, while I don't have any conficted PPAs or packages in the system.

I later marked it as invalid because I was able to fix it in my installation by removing the gnome-session package at first and the ubuntu-session afterwards (the other way around not working because gnome-session is a dependency for ubuntu-session) . Finally running upgrade & dist-upgrade installed the remaining packages without any issues and after that I was able to install the gnome-session package without any errors.

I only mention the above in case you think is useful for fixing this issue. So, the steps for fixing this in my system was:
sudo apt-get remove gnome-session
sudo apt-get remove ubuntu-session
sudo apt-get upgrade
sudo apt-get dist-upgrade
sudo apt-get install gnome-session

Hope this helps.

Best regards,
Elias

[Fabio Duran Verdugo (fabioduran)]

Yes with the elias explain solve the issues.