求救，我全新安装UBUNTU15.04一切正常，系统提示有更新可用，我就升级了，然后就杯具了，重启后，登录界面提示输入密码，我正确输入密码后，屏幕一闪又重新回到登录界面，一直这样无限循环！

我不知道

我也遇到过，我直接把主文件夹下的隐藏文件全部删除就行了，应该是哪里的配置文件冲突，我也没仔细辨别

看看 哪一個情況 比較接近

http://askubuntu.com/questions/614128/1 ... login-loop
15.04 and Nvidia: login loop

http://askubuntu.com/questions/613577/v ... flickering
Vivid Vervet upgrade mess - flickering

http://askubuntu.com/questions/612973/c ... 0-to-15-04
Caught in loop when trying to login after upgrade from 14.10 to 15.04

http://askubuntu.com/questions/613698/i ... cal-log-in
In Ubuntu 15.04 can't do graphical log in

http://askubuntu.com/questions/613701/u ... -interface
upgraded to 15.04 and can log onto command line but not graphical interface.

http://ubuntuforums.org/showthread.php?t=2268988
Login Loop After Update

https://bugs.launchpad.net/ubuntu/+sour ... ug/1432004
Nvidia broken after update on 15.04

https://www.reddit.com/r/Ubuntu/comment ... lieve_its/
Login loop after upgrading to 15.04.

http://ubuntuforums.org/showthread.php?t=2280651
Ubuntu 15.04 doesn't pass login screen

http://ubuntuforums.org/showthread.php?t=2217269
Desktop does not load after upgrading from 12.04 to 14.04 beta

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