Hello, This behavior (need to enter password 2 or 3 times) happened nearly from the beginning.
It is a fresh install of a standard xubuntu 16.04 LTS with my old homedir copied from the previous 16.04 machine (that has crashed). Packages are just installed when needed, so that forgotten packages are not borrowed from the old machine. Btw lightdm: 1.18.3-0ubuntu1.1 Today I had to enter my password 3 times. here are some extracts of 3 log files where I have found 2 errors in a short time : /var/log/syslog /var/log/lightdm/lightdm.log /var/log/lightdm/seat0-greeter.log Maybe useful information: When unlocked, I select the session with <Ctrl><Alt>7, but once locked, I have to select Ctrl><Alt>8; Or <Ctrl><Alt>7 displays a black screen with something in french like this: This session is locked you will be redirected to the unlock dialog automatically in a few seconds # Syslog: A connection to the bus can't be made tail -30 /var/log/syslog Jun 11 14:07:14 dlt0001ptrstp lightdm[1248]: ** (lightdm:1248): WARNING **: Error using VT_WAITACTIVE 7 on /dev/tty0: Interrupted system call Jun 11 14:07:14 dlt0001ptrstp org.gtk.vfs.Daemon[23411]: A connection to the bus can't be made Jun 11 14:07:15 dlt0001ptrstp systemd[1]: Started Session c32 of user lightdm. Jun 11 14:07:16 dlt0001ptrstp org.a11y.Bus[7986]: ** (process:7997): WARNING **: Failed to register client: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SessionManager was not provided by any .service files Jun 11 14:07:16 dlt0001ptrstp org.a11y.Bus[7986]: Activating service name='org.a11y.atspi.Registry' Jun 11 14:07:16 dlt0001ptrstp org.a11y.Bus[7986]: Successfully activated service 'org.a11y.atspi.Registry' Jun 11 14:07:16 dlt0001ptrstp org.a11y.atspi.Registry[8002]: SpiRegistry daemon is running with well-known name - org.a11y.atspi.Registry Jun 11 14:07:20 dlt0001ptrstp lightdm[1248]: ** (lightdm:1248): WARNING **: Error using VT_WAITACTIVE 7 on /dev/tty0: Interrupted system call Jun 11 14:07:20 dlt0001ptrstp org.gtk.vfs.Daemon[7986]: A connection to the bus can't be made Jun 11 14:07:21 dlt0001ptrstp systemd[1]: Started Session c33 of user lightdm. Jun 11 14:07:21 dlt0001ptrstp org.a11y.Bus[8079]: ** (process:8090): WARNING **: Failed to register client: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.gnome.SessionManager was not provided by any .service files Jun 11 14:07:21 dlt0001ptrstp org.a11y.Bus[8079]: Activating service name='org.a11y.atspi.Registry' Jun 11 14:07:22 dlt0001ptrstp org.a11y.Bus[8079]: Successfully activated service 'org.a11y.atspi.Registry' Jun 11 14:07:22 dlt0001ptrstp org.a11y.atspi.Registry[8095]: SpiRegistry daemon is running with well-known name - org.a11y.atspi.Registry Jun 11 14:07:27 dlt0001ptrstp org.gtk.vfs.Daemon[8079]: A connection to the bus can't be made # /var/log/lightdm/lightdm.log : Error using VT_WAITACTIVE [+1635057.87s] DEBUG: Continue authentication [+1635057.90s] DEBUG: Session pid=23480: Authentication complete with return value 0: Success [+1635057.90s] DEBUG: Authenticate result for user <user>: Success [+1635057.90s] DEBUG: User <user> authorized [+1635057.90s] DEBUG: Greeter sets language fr_FR [+1635057.98s] DEBUG: Greeter requests session xubuntu [+1635057.98s] DEBUG: Seat seat0: Returning to existing user session <user> [+1635057.98s] DEBUG: Unlocking login1 session c24 [+1635057.98s] DEBUG: Activating VT 7 [+1635057.98s] WARNING: Error using VT_WAITACTIVE 7 on /dev/tty0: Interrupted system call [+1635057.98s] DEBUG: Seat seat0: Stopping greeter [+1635057.98s] DEBUG: Session pid=23399: Sending SIGTERM [+1635057.98s] DEBUG: Activating login1 session c24 [+1635057.99s] DEBUG: Session pid=23480: Exited with return value 0 [+1635057.99s] DEBUG: Seat seat0: Session stopped [+1635058.00s] DEBUG: Greeter closed communication channel [+1635058.00s] DEBUG: Session pid=23399: Exited with return value 0 [+1635058.00s] DEBUG: Seat seat0: Session stopped [+1635058.00s] DEBUG: Seat seat0: Stopping display server, no sessions require it [+1635058.00s] DEBUG: Sending signal 15 to process 23391 [+1635058.32s] DEBUG: Process 23391 exited with return value 0 [+1635058.32s] DEBUG: DisplayServer x-1: X server stopped [+1635058.32s] DEBUG: Releasing VT 8 [+1635058.32s] DEBUG: DisplayServer x-1: Removing X server authority /var/run/lightdm/root/:1 [+1635058.32s] DEBUG: Seat seat0: Display server stopped [+1635058.32s] DEBUG: Seat seat0: Active display server stopped, starting greeter [+1635058.32s] DEBUG: Seat seat0: Creating greeter session [+1635058.32s] DEBUG: Seat seat0: Creating display server of type x [+1635058.32s] DEBUG: Using VT 8 [+1635058.32s] DEBUG: Seat seat0: Starting local X display on VT 8 [+1635058.32s] DEBUG: DisplayServer x-1: Logging to /var/log/lightdm/x-1.log [+1635058.32s] DEBUG: DisplayServer x-1: Writing X server authority to /var/run/lightdm/root/:1 [+1635058.32s] DEBUG: DisplayServer x-1: Launching X Server [+1635058.32s] DEBUG: Launching process 7966: /usr/bin/X -core :1 -seat seat0 -auth /var/run/lightdm/root/:1 -nolisten tcp vt8 -novtswitch [+1635058.32s] DEBUG: DisplayServer x-1: Waiting for ready signal from X server :1 [+1635058.95s] DEBUG: Got signal 10 from process 7966 [+1635058.95s] DEBUG: DisplayServer x-1: Got signal from X server :1 [+1635058.95s] DEBUG: DisplayServer x-1: Connecting to XServer :1 [+1635059.00s] DEBUG: Seat seat0: Display server ready, starting session authentication [+1635059.00s] DEBUG: Session pid=7974: Started with service 'lightdm-greeter', username 'lightdm' [+1635059.02s] DEBUG: Session pid=7974: Authentication complete with return value 0: Success [+1635059.02s] DEBUG: Seat seat0: Session authenticated, running command [+1635059.02s] DEBUG: Session pid=7974: Running command /usr/lib/lightdm/lightdm-greeter-session /usr/sbin/lightdm-gtk-greeter [+1635059.02s] DEBUG: Creating shared data directory /var/lib/lightdm-data/lightdm [+1635059.02s] DEBUG: Session pid=7974: Logging to /var/log/lightdm/seat0-greeter.log [+1635059.05s] DEBUG: Activating VT 8 ... [+1635070.71s] DEBUG: Authenticate result for user <user>: Success [+1635070.71s] DEBUG: User <user> authorized [+1635070.71s] DEBUG: Greeter sets language fr_FR [+1635070.76s] DEBUG: Greeter requests session xubuntu [+1635070.76s] DEBUG: Seat seat0: Returning to existing user session <user> [+1635070.76s] DEBUG: Unlocking login1 session c24 [+1635070.77s] DEBUG: Activating VT 7 [+1635070.98s] DEBUG: Seat seat0: Stopping greeter [+1635070.98s] DEBUG: Session pid=8067: Sending SIGTERM [+1635070.98s] DEBUG: Activating login1 session c24 [+1635070.99s] DEBUG: Session pid=8146: Exited with return value 0 [+1635070.99s] DEBUG: Seat seat0: Session stopped [+1635070.99s] DEBUG: Seat seat0 changes active session to c24 [+1635070.99s] DEBUG: Session c24 is already active [+1635070.99s] DEBUG: Session pid=8067: Exited with return value 0 [+1635070.99s] DEBUG: Seat seat0: Session stopped [+1635070.99s] DEBUG: Seat seat0: Stopping display server, no sessions require it [+1635070.99s] DEBUG: Sending signal 15 to process 8059 [+1635071.03s] DEBUG: Process 8059 exited with return value 0 [+1635071.03s] DEBUG: DisplayServer x-1: X server stopped [+1635071.03s] DEBUG: Releasing VT 8 [+1635071.03s] DEBUG: DisplayServer x-1: Removing X server authority /var/run/lightdm/root/:1 [+1635071.03s] DEBUG: Seat seat0: Display server stopped # /var/log/lightdm/seat0-greeter.log : indicator-application killed by TERM / process indicator-application stopped with state 1 ** (lightdm-gtk-greeter:23412): WARNING **: [PIDs] Failed to terminate process #23414: Aucun processus de ce type upstart: Le processus indicator-application main (23461) a été tué par le signal TERM ** Message: Starting lightdm-gtk-greeter 2.0.1 (Apr 11 2016, 06:05:31) ** Message: [Configuration] Reading file: /usr/share/lightdm/lightdm-gtk-greeter.conf.d/01_ubuntu.conf ** Message: [Configuration] Reading file: /usr/share/lightdm/lightdm-gtk-greeter.conf.d/30_xubuntu.conf ** Message: [Configuration] Reading file: /etc/lightdm/lightdm-gtk-greeter.conf upstart: Le processus indicator-application main (8037) a été tué par le signal TERM upstart: Le processus indicator-application main s'est achevé, redémarrage ** (lightdm-gtk-greeter:7987): WARNING **: [PIDs] Failed to terminate process #7989: Aucun processus de ce type ** Message: Starting lightdm-gtk-greeter 2.0.1 (Apr 11 2016, 06:05:31) ** Message: [Configuration] Reading file: /usr/share/lightdm/lightdm-gtk-greeter.conf.d/01_ubuntu.conf ** Message: [Configuration] Reading file: /usr/share/lightdm/lightdm-gtk-greeter.conf.d/30_xubuntu.conf ** Message: [Configuration] Reading file: /etc/lightdm/lightdm-gtk-greeter.conf upstart: Le processus indicator-application main (8126) s'est achevé avec l'état 1 upstart: Le processus indicator-application main s'est achevé, redémarrage upstart: Le processus indicator-messages main s'est achevé, redémarrage ** (lightdm-gtk-greeter:8080): WARNING **: [PIDs] Failed to terminate process #8082: Aucun processus de ce type upstart: Le processus indicator-messages main (8152) a été tué par le signal TERM upstart: Le processus indicator-application main (8151) a été tué par le signal TERM Regards, -- Stephane Peters. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/913323 Title: Occasional login failure and artefacts To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/lightdm/+bug/913323/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs