I used to modify /etc/lightdm/lightdm.conf, adding the line greeter-show-manual-login=true, in order to allow login for hidden users and root.
Now I've just installed the new Ubuntu 14.04 and the file lightdm.conf is no longer located in /etc/lightdm. It's in /etc/init and has been totally modified.
How can I force lightdm login screen to show a field to input a login name?
Ok I finally found the solution, very simple. The file to edit is now located in /usr/share/lightdm/lightdm.conf.d, and is called: 50-ubuntu.conf.
I just added the line:
greeter-show-manual-login=true
and on next reboot I was able to input any user name on the login screen.
I also had the same issue with Ubuntu 14.04 installation. But I resolved the problem by following this site.
The solution is to create a file lightdm.conf inside /etc/lightdm/ and put the following contents in it:
[SeatDefaults]
greeter-show-manual-login=true
After a system reboot, I was able to login with other users.
Also you should do following step:
update /etc/pam.d/common-session and change the line:
session sufficient pam_lsass.so
to:
session [success=ok default=ignore] pam_lsass.s
After a reboot, my path was ok, and everything seems to be working as normal again.
See the bug report
In addition to the greeter-show-manual-login=true option, one could use greeter-hide-users=true. Personally that's that I have in my /etc/lightdm/lightdm.conf : the manual login option is commented out, with only hide users option left.
