As mentioned in the logs, the problem is not due to ca-certificates but to lubuntu-software-center.
** Changed in: ca-certificates (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to ca-certificates in Ubuntu. https://bugs.launchpad.net/bugs/1494555 Title: package ca-certificates 20150426ubuntu1 failed to install/upgrade: bloqué en boucle sur le traitement des actions différées (« triggers »), abandon Status in ca-certificates package in Ubuntu: Incomplete Bug description: no ProblemType: Package DistroRelease: Ubuntu 15.10 Package: ca-certificates 20150426ubuntu1 ProcVersionSignature: Ubuntu 3.19.0-22.22-generic 3.19.8-ckt1 Uname: Linux 3.19.0-22-generic i686 ApportVersion: 2.18.1-0ubuntu1 Architecture: i386 Date: Fri Sep 11 00:06:56 2015 DuplicateSignature: package:ca-certificates:20150426ubuntu1:bloqué en boucle sur le traitement des actions différées (« triggers »), abandon ErrorMessage: bloqué en boucle sur le traitement des actions différées (« triggers »), abandon InstallationDate: Installed on 2015-09-10 (0 days ago) InstallationMedia: Lubuntu 15.10 "Wily Werewolf" - Alpha i386 (20150622) PackageArchitecture: all RelatedPackageVersions: dpkg 1.18.2ubuntu3 apt 1.0.9.10ubuntu6 SourcePackage: ca-certificates Title: package ca-certificates 20150426ubuntu1 failed to install/upgrade: bloqué en boucle sur le traitement des actions différées (« triggers »), abandon UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ca-certificates/+bug/1494555/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp