Fixing the Dreaded "Errors were encountered while processing" Errors

For the past week or two, every time I installed new software into Ubuntu, I was greeted with the “Errors were encountered while processing:” blah, blah, blah speech.

Up until yesterday, that error was just a battle scar my computer had earned attempting to install a few software packages. I didn’t need them, my computer wasn’t bothered by them not being fully installed so after trying to fix them many times I thought f#ck it! No real problem. But yesterday, when a few more packages failed to install, and this time they stopped my computer from updating itself and prevented me from using Synaptic, I decided enough is enough, I’m going to fix it once and for all. So, I tooled up, got out my best keyboard, readied my fastest mouse, donned my Linux badges and set out on my quest to kill the Big Bad Bug, save the princess and live happily ever after…. sorry, got a little carried away there.

Today, I completed my quest – I squished that bug and watched his juices spit all over my computer’s insides as it made that squelchy noise only squished bugs know how to make so well.

The next time you find you cannot add software into your Ubuntu distro because you’re getting errors that look like or totally unlike this one:

Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 38 not upgraded.
4 not fully installed or removed.
Need to get 0B/590kB of archives.
After this operation, 0B of additional disk space will be used.
WARNING: The following packages cannot be authenticated!
python-distutils-extra scons
Authentication warning overridden.
Selecting previously deselected package python-distutils-extra.
(Reading database ... 458474 files and directories currently installed.)
Preparing to replace python-distutils-extra 2.12 (using .../python-distutils-extra_2.12_all.deb) ...
dpkg (subprocess): unable to execute old pre-removal script: Exec format error
dpkg: warning: old pre-removal script returned error exit status 2
dpkg - trying script from the new package instead ...
Traceback (most recent call last):
File "/usr/bin/pycentral", line 2196, in <module>
main()
File "/usr/bin/pycentral", line 2190, in main
rv = action.run(global_options)
File "/usr/bin/pycentral", line 1645, in run
pkg = DebPackage('package', self.args[0], oldstyle=False)
File "/usr/bin/pycentral", line 381, in __init__
self.read_pyfiles()
File "/usr/bin/pycentral", line 414, in read_pyfiles
self.pkgconfig.set('pycentral', 'include-links', '0')
File "/usr/lib/python2.6/ConfigParser.py", line 669, in set
ConfigParser.set(self, section, option, value)
File "/usr/lib/python2.6/ConfigParser.py", line 377, in set
raise NoSectionError(section)
ConfigParser.NoSectionError: No section: 'pycentral'
dpkg: error processing /var/cache/apt/archives/python-distutils-extra_2.12_all.deb (--unpack):
subprocess new pre-removal script returned error exit status 1
dpkg (subprocess): unable to execute installed post-installation script: Exec format error
dpkg: error while cleaning up:
subprocess installed post-installation script returned error exit status 2
Preparing to replace scons 1.2.0-2ubuntu1 (using .../scons_1.2.0-2ubuntu1_all.deb) ...
dpkg (subprocess): unable to execute old pre-removal script: Exec format error
dpkg: warning: old pre-removal script returned error exit status 2
dpkg - trying script from the new package instead ...
Traceback (most recent call last):
File "/usr/bin/pycentral", line 2196, in <module>
main()
File "/usr/bin/pycentral", line 2190, in main
rv = action.run(global_options)
File "/usr/bin/pycentral", line 1645, in run
pkg = DebPackage('package', self.args[0], oldstyle=False)
File "/usr/bin/pycentral", line 381, in __init__
self.read_pyfiles()
File "/usr/bin/pycentral", line 414, in read_pyfiles
self.pkgconfig.set('pycentral', 'include-links', '0')
File "/usr/lib/python2.6/ConfigParser.py", line 669, in set
ConfigParser.set(self, section, option, value)
File "/usr/lib/python2.6/ConfigParser.py", line 377, in set
raise NoSectionError(section)
ConfigParser.NoSectionError: No section: 'pycentral'
dpkg: error processing /var/cache/apt/archives/scons_1.2.0-2ubuntu1_all.deb (--unpack):
subprocess new pre-removal script returned error exit status 1
dpkg (subprocess): unable to execute installed post-installation script: Exec format error
dpkg: error while cleaning up:
subprocess installed post-installation script returned error exit status 2
Errors were encountered while processing:
/var/cache/apt/archives/python-distutils-extra_2.12_all.deb
/var/cache/apt/archives/scons_1.2.0-2ubuntu1_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

Use these steps to fix them:

Firstly, make a note of the applications that refuse to install then try one or more of the usual hit-n-stab gambits before pulling out your longsword and making more extensive blood letting cuts into your system:

ensure that the shared libraries are properly registered (also fixes some GCC/G++ errors)

sudo ldconfig

try to remove the package (replace ‘your-app’ with the name of the dodgy application)

sudo dpkg -r YOUR-APP

check your package cache

sudo apt-get check

update your package list

sudo apt-get update

ensure package downloads were properly completed when the system last updated

sudo apt-get upgrade --fix-missing

try to upgrade the system (sometimes an updated package version fixes the issue)

sudo apt-get upgrade
sudo apt-get dist-upgrade

try to reconfigure all applications that failed to install

sudo dpkg --configure -a

try to reconfigure specific applications that failed to install

sudo dpkg --configure YOUR-APP

try to fix broken packages

sudo apt-get install -f

try to fix a specific broken package

sudo apt-get install YOUR-APP -f

try to install the dependencies that an application requires for it to install successfully

sudo apt-get build-dep YOUR-APP

re-try to install the failed apps

sudo apt-get install

If none of the above fix it, try this:

Go to the website that maintains the failed package. In most cases, this will be Launchpad.net (for Ubuntu flavors, go here); users of Debian distros (inc. Ubuntu) can download source code packages from Debian.org and a lot of packages for all distros are maintained through Gna. If you’re really stuck, Google it;
Search for the failed package then re-download it and re-install it. First try the deb package that is pre-built for your OS version then, if that doesn’t work, download the source code and build it from scratch;
```
./configure
make
make install
```
```
python setup.py install
```
```
sudo ldconfig
```

If you struggle to install the downloaded source code you can read this Linux Software Installation EasyGuide. The downside to installing from source code (i.e not through Apt, Aptitude, Yum or dpkg) is that your regular package manager will not know that the software has been installed. Just re-install it through your regular package manager once it is functioning properly.

If you are still battling away after trying the above then you have no choice but to bring out your longsword and start swinging at dpkg’s bowels:

backup your dpkg status file with

sudo cp /var/lib/dpkg/status status.bckup

just for reference, if you need to restore the backup version of the status file, type

sudo mv status.bckup > /var/lib/dpkg/status

edit your dpkg status file

KDE Users

kdesudo kate /var/lib/dpkg/status

Gnome users

gksu gedit /var/lib/dpkg/status

search for the problem package(s) by name (press Ctrl+F),
edit the line that reads

Status: install reinstreq half-configured

to replace it with

Status: install ok installed

and save it,

then either uninstall the package(s) then/or re-install it(them) with either

sudo apt-get remove YOUR-APP

else

sudo apt-get install YOUR-APP

If the problem persists, re-edit /var/lib/dpkg/status but this time search for the failed package by name and delete its details from

Package....

Description....

Delete from the open line above package to the open line below its description that leads on to the next package’s details. Here is an example of the complete package listing for ‘lsb-core’:

Package: lsb-core
Status: install ok installed
Priority: extra
Section: misc
Installed-Size: 196
Maintainer: Ubuntu Core Developers <ubuntu-devel-discuss@lists.ubuntu.com>
Architecture: amd64
Source: lsb
Version: 4.0-0ubuntu5
Replaces: lsb (<< 2.0-2)
Provides: lsb-core-amd64, lsb-core-noarch
Depends: lsb-release, libc6 (>> 2.3.5), libz1, libncurses5, libpam0g, postfix | mail-transport-agent, at, bc, binutils, bsdmainutils, bsdutils, cpio, cron, ed, file, libc6-dev | libc-dev, locales, cups-bsd | lpr, lprng | cups-client, m4, mailx | mailutils, make, man-db, mawk | gawk, ncurses-term, passwd, patch, pax, procps, psmisc, rsync, alien (>= 8.36), python, python-central (>= 0.6.11), debconf (>= 0.5) | debconf-2.0, libc6-i386, lib32z1, lsb-base, time
Conflicts: lsb (<< 2.0-2)
Description: Linux Standard Base 4.0 core support package
The Linux Standard Base (http://www.linuxbase.org/) is a standard
core system that third-party applications written for Linux can
depend upon.
.
This package provides an implementation of the core of version 4.0 of
the Linux Standard Base for Debian on the Intel x86, Intel ia64
(Itanium), IBM S390, and PowerPC 32-bit architectures with the Linux
kernel. Future revisions of the specification and this package may
support the LSB on additional architectures and kernels.
.
The intent of this package is to provide a best current practice way
of installing and running LSB packages on Debian GNU/Linux. Its
presence does not imply that Debian fully complies
with the Linux Standard Base, and should not be construed as a
statement that Debian is LSB-compliant.
Homepage: http://www.linux-foundation.org/en/LSB
Original-Maintainer: Chris Lawrence <lawrencc@debian.org>
Python-Version: all

That whole section would be deleted were lsb-core an issue on your system.

When you update your package list you will notice that those packages with their details removed from dpkg’s status file will not now show as installed by dpkg. Rest assured, those packages are still installed/semi-installed but dpkg is no longer aware of them. At this point you can choose to either ‘re-install’ the badly installed package or just leave it hanging on your system as an undetected badly installed package which you should try to re-install at a later time. I recommend you try to re-install immediately. If you leave it as an undetected package, dpkg will not automatically update it and will try to re-install it should it be a dependency of other packages that you later try to install.

If none of those steps fix it then the likelihood is that nothing will but search the net before you decide to re-install your operating system.

As a word of caution, never, ever delete your dpkg (apt) status file. If someone tells you to type

sudo rm /var/lib/dpkg/status

Ignore them or your computer will explode! You can open it up, look at it and edit it but you must never, ever delete it. It contains all the data dpkg requires to update and uninstall packages. If you delete it you will not be able to properly remove or upgrade the packages installed prior to it being removed and you might have problems when you try to install new packages into your system.

Bootnote: You can use Aptitude to “Hold” partially installed packages and packages that prevent others from being installed. Open a terminal, type “sudo aptitude”, press “Ctrl+T” then “Return”, use the arrow keys to navigate to the suspect package, press the “equals” key i.e “=” (the package to be held should now change color), press Ctrl+T then press return and any packages that are ready to install but were stuck due to the (now) held package will now install.

Visit the Software Installation EasyGuide for more installation error busters and the Ubuntu Repository List to get extra useful repositories for your system.