The reported error is fixed by changing the line 814 In file /usr/bin /unattended-upgrade
subject = _("unattended-upgrades result for '%s': '%s'") % ( host(), res) into subject = _("unattended-upgrades result for '{}': '{}'").format( host(), res) Unfortunately the % formating is used in many places and changing this line doesn't definitely fix the problem with unattended-updates. Worse. Every time unattended-upgrades tries to upgrade packages I end up with a broken package. I need to use synaptic to fix the broken package. Not sure if it is properly fixed. Could someone please fix this issue ? This means people don't get their packages automatically upgraded. Doing it manually fails because of the broken package. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unattended-upgrades in Ubuntu. https://bugs.launchpad.net/bugs/1527106 Title: Fatal exception failure of unattended-upgrade Status in unattended-upgrades package in Ubuntu: Incomplete Bug description: Every morning, since I upgraded to Ubuntu 15.10, IĀ get a mail (root) reporting a fatal exception in unatteded-upgrade containing the following. /etc/cron.daily/apt: Exception: unsupported operand type(s) for %: 'bytes' and 'tuple' Traceback (most recent call last): File "/usr/bin/unattended-upgrade", line 1435, in <module> main(options) File "/usr/bin/unattended-upgrade", line 1382, in main pkgs, pkg_install_success, pkgs_kept_back, mem_log, log_content) File "/usr/bin/unattended-upgrade", line 815, in send_summary_mail host(), res) TypeError: unsupported operand type(s) for %: 'bytes' and 'tuple' As a consequence no automatic updates are performed anymore, including security updates. For this reason I flag this as a security vulnerability although it is only indirect. Manual updates is still working. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unattended-upgrades/+bug/1527106/+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