ubuntu16.04 Login Interface Enter user name password and return to login interface

There are several reasons for this:

It is best to look at the log first,/var/log/xorg.0.log.

1, there is not enough disk space.

Solution: Character interface login, delete some files, free up some space, restart can be.

The permissions issue for the 2,/home/username folder.

Solution: # chown Username:username/home/username-r

The permissions issue for the 3,/tmp folder.

Workaround: Change to the permissions shown below.

$ ls/-lt
Total 280
DRWXRWXRWT root root 155648 Aug 19:47 tmp

4, ~/. Xauthority File Permissions Issues

Solution: 1>, deleting the file

Or 2>, # chown Username:username ~/. Xauthority

You can also view log files ~/.xsession-errors

5, the cause of the circular landing may also be. Profile or profile was changed.

Workaround: Copy one of the files from another Ubuntu system.

$ cat ~/.profile
# ~/.profile:executed by the command interpreter for login shells.
# This file is not read by Bash (1), if ~/.bash_profile or ~/.bash_login
# exists.
# See/usr/share/doc/bash/examples/startup-files for examples.
# The files are located in the Bash-doc package.


# The default umask is set in/etc/profile; For setting the Umask
# for SSH logins, install and configure the Libpam-umask package.
#umask 022


# If running bash
If [-N "$BASH _version"]; Then
# include. BASHRC if it exists
If [f "$HOME/.BASHRC"]; Then
. "$HOME/.BASHRC"
Fi
Fi


# set PATH so it includes user ' s private bin if it exists
If [-D "$HOME/bin"]; Then
Path= "$HOME/bin: $PATH"
Fi

6, if you have previously installed the NVIDIA graphics driver, you can reinstall the video driver (possibly the video driver is not fully installed successfully, resulting in the video card driver's profile part of the damage, resulting in the inability to access the desktop).

WORKAROUND: Reinstall the video driver.

Listed above are just a few of the common situations, welcome to add in comments.

There is a proposal to install the driver, plus the following flags (original URL: Http://blog.csdn.net/chaihuimin/article/details/71006654?locationNum=2&fps=1):

sudo./nvidia.run-no-x-check-no-nouveau-check-no-opengl-files
-no-x-check: Turn off x service when driver is installed
-no-nouveau-check: Disable Nouveau when installing drivers
-no-opengl-files: Only driver files are installed, OpenGL files are not installed
If you do this again, there is no question of looping reboot.