package libqt5webkit5:amd64 5.4.2+dfsg-1ubuntu2.1 failed to install/upgrade: package libqt5webkit5:amd64 is not ready for configuration cannot configure (current status 'half-installed')

[Massimo Luraschi]

I was trying to install unity tweak tool, after performing updates right after a fresh install. There seemed to be a problem with dpkg and lightdm, so I restarted the PC. After restarting, I get this error.

ProblemType: Package
DistroRelease: Ubuntu 15.10
Package: libqt5webkit5:amd64 5.4.2+dfsg-1ubuntu2.1
ProcVersionSignature: Ubuntu 4.2.0-34.39-generic 4.2.8-ckt4
Uname: Linux 4.2.0-34-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.19.1-0ubuntu5
AptOrdering:
 libqt5webkit5: Configure
 NULL: ConfigurePending
Architecture: amd64
Date: Wed Mar 30 00:12:56 2016
DpkgTerminalLog:
 dpkg: error processing package libqt5webkit5:amd64 (--configure):
  package libqt5webkit5:amd64 is not ready for configuration
  cannot configure (current status 'half-installed')
DuplicateSignature: package:libqt5webkit5:amd64:5.4.2+dfsg-1ubuntu2.1:package libqt5webkit5:amd64 is not ready for configuration cannot configure (current status 'half-installed')
ErrorMessage: package libqt5webkit5:amd64 is not ready for configuration cannot configure (current status 'half-installed')
InstallationDate: Installed on 2016-03-29 (0 days ago)
InstallationMedia: Ubuntu-GNOME 15.10 "Wily Werewolf" - Release amd64 (20151021)
RelatedPackageVersions:
 dpkg 1.18.2ubuntu5.1
 apt 1.0.10.2ubuntu1
SourcePackage: qtwebkit-opensource-src
Title: package libqt5webkit5:amd64 5.4.2+dfsg-1ubuntu2.1 failed to install/upgrade: package libqt5webkit5:amd64 is not ready for configuration cannot configure (current status 'half-installed')
UpgradeStatus: No upgrade log present (probably fresh install)