I consistently get two login screens

Question

I consistently get two login screens!

I enter credentials correctly and am immediately presented with a second login screen (no errors). Authenticating against the second screen completes a normal login to the Ubuntu desktop.

The above is a quotation from a problem reported on 7. May 2012 by Soren Mogensen. See User login cycles. I have the exact same problem, and was hoping that Soren might have received an answer which would enlighten others, but unfortunately Soren's problem was reported as part of an "answer" to another problem, and the only "solution" on that occasion was advice to create a new question.

I can login, I just have to present my credentials twice, so this is NOT a duplicate of any "unable to login" problem. My concern is that this looks like a classic phishing setup, where one of the two login screens is a fake designed to harvest my ID and password for some nefarious purpose. If Ubuntu has been susceptible to phishing attacks for nearly a year now, then I imagine that would be a matter of enormous concern.

Answer 1

Uninstall your gnome-screensaver,

sudo apt-get remove gnome-screensaver

Then, reboot. It works for me, now only unity login screen appears.

Answer 2

1. Try sudo pstree

   You should look for the Xorg process and see what parent it has. Is that parent process lightdm?

   Then you're using the LightDM display manager, and it's proboably a LightDM issue.

2. Install another display manager, GDM

   sudo apt-get install gdm
   

   During configuration of the package, set GDM as the display manager.

   Does the problem still exist? Now you're sure it's a LightDM issue.

3. sudo dpkg-reconfigure lightdm
   

   Now LigthDM is back.

Answer 3

Turn off Screen Reader

To do this:

1. Go to System Settings > Universal Access
2. Under the Seeing tab, turn OFF- Screen Reader

Answer 4

This solution seems to work for some as it looks like an ongoing problem depending on circumstances - Look in your system settings for "Lock Screen" in all possible applications.

1. Search dash or in system settings go to Brightness & Lock then turn lock off.

2. Check in other apps like Unity Tweak Tool > System and uncheck Desktop lock.

3. Open a terminal and navigate to /var/log/ then use less auth.log and check the log then check to see what happens at start if there any errors. Look out for pam-wallet issues like directory not found, error opening it. If you see wallet errors then try reinstalling - sudo apt-get install --reinstall pam-kwallet then sudo apt-get -f install && sudo apt-get autoremove && sudo apt-get -y autoclean && sudo apt-get -y clean finally sudo apt-get update. Reboot machine.

4. Reconfigure lightdm using commands below one by one

   sudo apt-get purge lightdm
   sudo apt-get install
   sudo apt-get install lightdm
   sudo dpkg-reconfigure gdm