Now, I found its solution for me It does not happen when I use two language for input one is ubuntu default language (mother language) Korean (Hangul) second is english to input command, password, etc....
At the lock screen, without english , I can't type password it is the very first reason for this issue but, after I add english for input language it changed automatically to english , and it makes me enable to type password where to report this issue? i will suggest it for related to ubuntu language input method team -- You received this bug notification because you are a member of DX Packages, which is subscribed to unity in Ubuntu. Matching subscriptions: dx-packages https://bugs.launchpad.net/bugs/1251213 Title: From the lock screen , It happened to unable to type password Status in “unity” package in Ubuntu: Confirmed Bug description: From the lock screen , It happened to unable to type password ProblemType: Bug DistroRelease: Ubuntu 14.04 Package: gnome-screensaver 3.6.1-0ubuntu7 ProcVersionSignature: Ubuntu 3.12.0-2.7-generic 3.12.0 Uname: Linux 3.12.0-2-generic i686 NonfreeKernelModules: nvidia ApportVersion: 2.12.6-0ubuntu1 Architecture: i386 Date: Thu Nov 14 20:53:05 2013 GnomeSessionIdleInhibited: No GnomeSessionInhibitors: None GsettingsGnomeSession: org.gnome.desktop.session idle-delay uint32 300 org.gnome.desktop.session session-name 'ubuntu' InstallationDate: Installed on 2013-11-13 (0 days ago) InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Alpha i386 (20131113) MarkForUpload: True SourcePackage: gnome-screensaver UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unity/+bug/1251213/+subscriptions -- Mailing list: https://launchpad.net/~dx-packages Post to : dx-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~dx-packages More help : https://help.launchpad.net/ListHelp