39

I'm on Ubuntu 18.04 and since today whenever I lock my system and try to log back in using my password, it shows the 'in progress' spinner for few seconds then I get the error message "Authentication error". I can successfully log in on the first start though.

I have tried to force disable Wayland by uncommenting the line #WaylandEnable=false to WaylandEnable=false in /etc/gdm3/custom.conf but it had no effect. I was originally using Xorg as well.

I've checked for any available system updates in hope of getting a fix but none are available. What can I do to investigate into and fix this error?

Update: I re-installed Ubuntu 18.04 to get rid of the issue.

Harshil Sharma
  • 553

9 Answers9

18

You can unlock the screen from terminal and command line, avoiding reboot. This is a temporary solution while you work on a permanent one.

On the login screen, Press Ctrl + Alt + F3 to open a terminal, or use SSH to access from another computer. To unlock all sessions, type sudo loginctl unlock-sessions. Then press Ctrl + Alt + F2, for example, to go back to your (now unlocked) session.

For more details, please see Unlock login screen using command line

This does not solve the underlying problem, but lets you quickly get back to your session to save your work and try configuration changes, without having to reboot.

Pablo Bianchi
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saeng
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14

The sudo dpkg-reconfigure gnome-shell command did not work for me.

What did work was changing fs.inotify.max_user_watches. I used this solution (also here).

Temporary solution

sudo sysctl -w fs.inotify.max_user_watches=524288  # sysctl - configure kernel parameters at runtime

or

sudo -i
echo 1048576 > /proc/sys/fs/inotify/max_user_watches
exit

Permanent solution

Modifying /etc/sysctl.conf:

sudo echo "fs.inotify.max_user_watches=524288" >> /etc/sysctl.conf

Related

Pablo Bianchi
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slimbob
  • 141
11

I had the same problem. After running the following I can re-login from the lock screen.

sudo dpkg-reconfigure gnome-shell
Philip Weiss
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4

In order to resolve this issue open /etc/sysctl.conf file as root user in your favourite text edior. Now add fs.inotify.max_user_watches = 524288 at the bottom of the file and save it. Run sudo sysctl -p command in terminal to persist the changes you made in sysctl. And its done !

user34567
  • 141
3

I experienced the same issue and by heading into a new terminal (Ctrl+Alt+F3) I ran sudo service gdm restart which switched back to a graphical login. Logging in didn't work and the warning on the terminal said a warning about not being able to watch the file system, not enough disk space. The fix was increasing the max_user_watches as found in this article.

Stephen Rauch
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  • 15
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Dav
  • 513
2

Got this problem in Ubuntu 20, none of the solutions worked and I cannot even see the login screen after reboot....
Have to jump to the console by Ctrl+Alt+F1 to login through tty.

I solved this problem by reinstall gnome and ubuntu desktop in tty:

sudo apt-get install --reinstall ubuntu-desktop
sudo apt-get install --reinstall gnome-shell
zx485
  • 2,865
user2870288
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1

The gnome reconfigure command worked for me even after a completely clean reinstall failed. I had also tried to use the wayland log in and got stuck in a log in loop and had also tried to purge upstart which was apparently causing issues for some users.

robotsheepboy
  • 11
0

I had similar issue. I ran the following to ensure all my packages were up to date

  1. sudo apt update & apt upgrade

The above displayed a message "6 packages to upgrade" I then ran the following to do an upgrade.

  1. sudo apt full-upgrade

Then reboot my desktop.

  1. sudo reboot

After reboot, the login screen should allow you to enter the password.

MD TheCoder
  • 9
0

In my case, gnome wasn't proper. my error was dpkg: unrecoverable fatal error, aborting: unknown group 'geoclue' in statoverride file

So I had to go to statoverride and groupadd geoclue But still whatever files were there in statoverride file they were showing the same error, I had to groupadd all the groups, then sudo apt-get install --reinstall gnome-session ubuntu-desktop that's it. Took me almost whole day but it did work.

123boo
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