I've installed xubuntu-desktop metapackapge on my system and afted this action unity-greeter has gone away. Ive purged lightdm twisely, then installed lightdm and unity-greeter. But still no result. Copying all files from /usr/share/lightdm/lightdm.conf.d/ to /etc/lightdm/lightdm.conf.d/ returned my unite greeter. But it is uncontroolable. For example is asks my password each time after locking the screen. I've rechecked this iptions is system settings many times, but I can't tune my lightdm. How to get my lightdm and unity greeter back withiut reinstalling of the system?