Just happened to me. It hangs the entire upgrade and it is impossible to continue. The only thing you can do is to hard shut down the computer, and notice it no longer boots.
Trying to fix packages in any form does not fix the problem. ** Changed in: gconf (Ubuntu) Importance: High => Critical ** Changed in: gconf (Ubuntu) Status: Confirmed => Triaged -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gconf in Ubuntu. https://bugs.launchpad.net/bugs/1551623 Title: package gconf2 3.2.6-3ubuntu6 failed to install/upgrade: dependency problems - leaving triggers unprocessed Status in gconf package in Ubuntu: Triaged Bug description: When upgrading from 15.10 to 16.04Beta (2016-03-01), this error occured, alongside many others related to systemd and gnome. Notice that despite all warnings and errors, finally, the system remained functional. ProblemType: Package DistroRelease: Ubuntu 16.04 Package: gconf2 3.2.6-3ubuntu6 ProcVersionSignature: Ubuntu 4.4.0-8.23-generic 4.4.2 Uname: Linux 4.4.0-8-generic x86_64 ApportVersion: 2.20-0ubuntu3 Architecture: amd64 Date: Tue Mar 1 09:21:15 2016 ErrorMessage: dependency problems - leaving triggers unprocessed InstallationDate: Installed on 2015-10-04 (148 days ago) InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Alpha amd64 (20151002) RelatedPackageVersions: dpkg 1.18.4ubuntu1 apt 1.2.3 SourcePackage: gconf Title: package gconf2 3.2.6-3ubuntu6 failed to install/upgrade: dependency problems - leaving triggers unprocessed UpgradeStatus: Upgraded to xenial on 2016-03-01 (0 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gconf/+bug/1551623/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp