I confirm the same bug on own PC : Fresh install ubuntu-gnome 16.04.1 updated with Gnome 3.20 from ppa:gnome3-team/gnome3-staging
Jan 4 16:09:08 PC systemd[1]: Started CUPS Scheduler. Jan 4 16:09:08 PC colord[1309]: (colord:1309): Cd-WARNING **: failed to get session [pid 8407]: Aucun périphérique ou adresse Jan 4 16:15:09 PC gnome-settings-daemon.desktop[2008]: (gnome-settings-daemon:2008): color-plugin-WARNING **: failed to connect to device: Failed to connect to missing device /org/freedesktop/ColorManager/devices/cups_HP_Color_LaserJet_MFP_M476dn Jan 4 16:43:23 PC systemd[1]: Started CUPS Scheduler. Jan 4 16:43:23 PC colord[1309]: (colord:1309): Cd-WARNING **: failed to get session [pid 8945]: Aucun périphérique ou adresse Jan 4 16:49:25 PC gnome-settings-daemon.desktop[2008]: (gnome-settings-daemon:2008): color-plugin-WARNING **: failed to connect to device: Failed to connect to missing device /org/freedesktop/ColorManager/devices/cups_HP_Color_LaserJet_MFP_M476dn -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to gnome-settings-daemon in Ubuntu. https://bugs.launchpad.net/bugs/1635715 Title: failed to connect to device: Failed to connect to missing device /org/freedesktop/ColorManager/devices/cups_HP_LaserJet_1020 Status in gnome-settings-daemon package in Ubuntu: New Bug description: The complete errors that are shown together are: Oct 18 08:20:51 localhost systemd[1]: Started CUPS Scheduler. Oct 18 08:20:51 localhost gnome-session[1504]: (gnome-settings-daemon:1533): color-plugin-WARNING **: failed to connect to device: Failed to connect to missing device /org/freedesktop/ColorManager/devices/cups_HP_LaserJet_1020 Oct 18 08:20:51 localhost gnome-session[1504]: (gnome-settings-daemon:1533): color-plugin-WARNING **: failed to connect to device: Failed to connect to missing device /org/freedesktop/ColorManager/devices/cups_PDF Distributor ID: Ubuntu Description: Ubuntu 16.04.1 LTS Release: 16.04 Codename: xenial gnome-settings-daemon: Installed: 3.18.2-0ubuntu3.1 Candidate: 3.18.2-0ubuntu3.1 Version table: *** 3.18.2-0ubuntu3.1 500 500 http://us.archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages 100 /var/lib/dpkg/status 3.18.2-0ubuntu3 500 500 http://us.archive.ubuntu.com/ubuntu xenial/universe amd64 Packages This happens quite frequently and I'm not sure of the cause. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-settings-daemon/+bug/1635715/+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