Occasionally my lock screen does this:

No password input

That makes logging in difficult. Restarting Unity kind of works, sometimes only a reboot will fix it. My video card is a Sapphire Radeon HD 6870 with dual displays using the open drivers.

  • 4
    This might be a bug. Take a look at bugs.launchpad.net/ubuntu/+source/unity/+bug/1311316
    – Mitch
    Jul 3, 2014 at 8:35
  • Had the same problem, mostly occuring when training neural networks using Caffe. unity --replace makes the login screen go away, but everything else seems corrupted. So I still had to reboot :(
    – mcExchange
    Nov 10, 2015 at 9:00

4 Answers 4


Reloading unity restores the password input on the login screen for me (Ubuntu 14.04 with a Nvidia GPU).

  1. Switch to an alternate terminal using Ctrl+Alt+F1.

  2. Reload unity with:

    nohup unity --replace &
  3. Switch back to your graphical terminal using Ctrl+Alt+F7. You may have to wait several seconds if you see a black screen.

Unity sort of works after this but you can at least save your work in progress:

  • The compiz grid plugin seems to think multiple monitors are now a single monitor.

  • The global menu bar no longer works.

  • Menus in window title bars no longer work (if enabled).

  • Custom global keyboard shortcuts don't work.

  • Note: In more recent versions, the --replace option is deprecated. :(
    – BlueBomber
    Feb 13, 2015 at 19:06
  • This worked to recover my desktop but killed all my running task! I think I may have to part with Unity as it is not reliable. Jun 23, 2015 at 12:33
  • This has the strange side-effect of making me enter my password twice to log in. (14.04)
    – ashes999
    Jul 25, 2015 at 19:14
  • If nothing else works, try entering your username login in ALL LOWERCASE. I pulled my hair out before finally coming to this solution!
    – wesf90
    Oct 20, 2015 at 18:55
  • This works, albeit with the really hilarious side-effect of requiring me to enter my password twice whenever I unlock. As you said, sort of works, and rebooting is probably the best way to go.
    – ashes999
    May 7, 2017 at 12:46

I had the same problem on an HP with Radeon 6370 graphics. I'm still using open source graphics, but I'm using the versions that came from the oibaf repository - they are a little 'edgier' than the stock open source, but not as edgy as xorg-edgers.

sudo add-apt-repository ppa:oibaf/graphics-drivers
sudo apt-get update
sudo apt-get upgrade

installs the drivers

sudo apt-get install ppa-purge
sudo ppa-purge ppa:oibaf/graphics-drivers

removes the drivers.

  • Tried this one, and it didn't seem to work. Did I have to reboot after installing the new drivers? Jul 5, 2014 at 4:20
  • Yes you would need to reboot. Jul 5, 2014 at 14:20

open terminal

reset the unity

$ unity-reset
$ setsid unity 

if that didnt workout try to re-install the unity & the desktop

$ sudo apt-get autoremove ubuntu-desktop 
$ sudo apt-get autoremove unity 
$ sudo apt-get update 
$ sudo apt-get install unity
$ sudo apt-get install unity-2d 
$ sudo apt-get install ubuntu-desktop 
$ sudo shutdown -r

now install the ati driver

$ sudo add-apt-repository ppa:ubuntu-x-swat/x-updates
$ sudo apt-get update
$ sudo apt-get install fglrx gksu
$ sudo amdconfig --initial && sudo shutdown -r

after the reboot
u can run the driver buy ALT + F2
copy & past this

gksu amdcccle

This can be worked around without losing your session by:

  1. Switch to a tty (e.g. Ctrl+Alt+F1)
  2. Log in
  3. Run: sudo loginctl unlock-sessions
  4. Switch back to the Desktop: Ctrl+Alt+F7 (or F8).

From the bug report fori this issue and this answer to a similar question

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