tried to install wps ,couldn't and on every startup now I get this message :package libpng12-0 1.2.54-1ubuntu1 failed to install/upgrade: trying to overwrite shared '/usr/share/doc/libpng12-0/ANNOUNCE', which is different from other instances of package libpng12-0:amd64

[RAHUL TRIPATHY]

I tried to install wps office. couldn't as it said it needs some older version of libping12 which "could not be installed" so I purged the one and installed an older one. Now at every boot I get a crash report.

Ubuntu 16.04 LTS
Package info:
$ apt-cache policy libpng12-0

libpng12-0:
  Installed: 1.2.54-1ubuntu1
  Candidate: 1.2.54-1ubuntu1
  Version table:
 *** 1.2.54-1ubuntu1 500
        500 http://archive.ubuntu.com/ubuntu xenial/main amd64 Packages
        100 /var/lib/dpkg/status

ProblemType: Package
DistroRelease: Ubuntu 16.04
Package: libpng12-0 1.2.54-1ubuntu1
ProcVersionSignature: Ubuntu 4.4.0-97.120-generic 4.4.87
Uname: Linux 4.4.0-97-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.20.1-0ubuntu2.10
Architecture: amd64
Date: Fri Nov 17 12:21:37 2017
Dependencies:
 gcc-6-base 6.0.1-0ubuntu1
 libc6 2.23-0ubuntu9 [origin: unknown]
 libgcc1 1:6.0.1-0ubuntu1
 zlib1g 1:1.2.8.dfsg-2ubuntu4.1 [origin: unknown]
DpkgTerminalLog:
 Preparing to unpack .../libpng12-0_1.2.54-1ubuntu1_amd64.deb ...
 Unpacking libpng12-0:amd64 (1.2.54-1ubuntu1) over (1.2.50-2+deb8u3) ...
 dpkg: error processing archive /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1_amd64.deb (--unpack):
  trying to overwrite shared '/usr/share/doc/libpng12-0/ANNOUNCE', which is different from other instances of package libpng12-0:amd64
DuplicateSignature:
 package:libpng12-0:1.2.54-1ubuntu1
 Unpacking libpng12-0:amd64 (1.2.54-1ubuntu1) over (1.2.50-2+deb8u3) ...
 dpkg: error processing archive /var/cache/apt/archives/libpng12-0_1.2.54-1ubuntu1_amd64.deb (--unpack):
  trying to overwrite shared '/usr/share/doc/libpng12-0/ANNOUNCE', which is different from other instances of package libpng12-0:amd64
ErrorMessage: trying to overwrite shared '/usr/share/doc/libpng12-0/ANNOUNCE', which is different from other instances of package libpng12-0:amd64
InstallationDate: Installed on 2017-04-22 (209 days ago)
InstallationMedia: Ubuntu 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
RelatedPackageVersions:
 dpkg 1.18.4ubuntu1.2
 apt 1.2.24
SourcePackage: libpng
Title: package libpng12-0 1.2.54-1ubuntu1 failed to install/upgrade: trying to overwrite shared '/usr/share/doc/libpng12-0/ANNOUNCE', which is different from other instances of package libpng12-0:amd64
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Kai Kasurinen (kai-kasurinen)]

libpng12-0:amd64 (1.2.50-2+deb8u3)

Thank you for taking the time to report this bug and trying to help make Ubuntu better. However, it seems that you are not using a software package provided by the official Ubuntu repositories. Because of this the Ubuntu project can not support or fix your particular bug. Please report this bug to the provider of the software package. Thanks!

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