package overlay-scrollbar 0.2.17.1+15.10.20150604.1-0ubuntu1 failed to install/upgrade: unable to securely remove '/usr/lib/i386-linux-gnu/gtk-3.0/modules/liboverlay-scrollbar.so': Not a directory

Ci sono stati degli errori di installazione.
Inoltre alla fine dell'installazione della nuova versione 15.10 è saltata la convalida dei certificati.

ProblemType: Package
DistroRelease: Ubuntu 15.10
Package: overlay-scrollbar 0.2.17.1+15.10.20150604.1-0ubuntu1
ProcVersionSignature: Ubuntu 3.19.0-30.34-generic 3.19.8-ckt6
Uname: Linux 3.19.0-30-generic i686
NonfreeKernelModules: nvidia
ApportVersion: 2.19.1-0ubuntu3
Architecture: i386
Date: Sun Oct 25 15:40:40 2015
DuplicateSignature: package:overlay-scrollbar:0.2.17.1+15.10.20150604.1-0ubuntu1:unable to securely remove '/usr/lib/i386-linux-gnu/gtk-3.0/modules/liboverlay-scrollbar.so': Not a directory
ErrorMessage: unable to securely remove '/usr/lib/i386-linux-gnu/gtk-3.0/modules/liboverlay-scrollbar.so': Not a directory
InstallationDate: Installed on 2014-10-28 (362 days ago)
InstallationMedia: Ubuntu 14.10 "Utopic Unicorn" - Release i386 (20141022.1)
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.18.2ubuntu5
 apt 1.0.10.2ubuntu1
SourcePackage: overlay-scrollbar
Title: package overlay-scrollbar 0.2.17.1+15.10.20150604.1-0ubuntu1 failed to install/upgrade: unable to securely remove '/usr/lib/i386-linux-gnu/gtk-3.0/modules/liboverlay-scrollbar.so': Not a directory
UpgradeStatus: Upgraded to wily on 2015-10-25 (0 days ago)