Ubuntu18 无法加载登录界面【100%解决】

Move xorg.conf file out of the way

If display settings have been corrupted or modified incorrectly, it's good to remove the xorg.conf.

mv /etc/X11/xorg.conf /etc/X11/xorg.conf.old

By default, X11 config files are instead stored here:

/usr/share/X11/xorg.conf.d

xorg.conf files saved in /etc/X11 can cause displays issues on boot, and should be avoided wherever possible.

After moving those files and rebooting, try logging in again. (There may be files you need to move other than the common ones listed above.)

Reinstall the login manager

You can reinstall GNOME Display Manager (which handles the login screen), along with the desktop environment by running the below commands in :

sudo apt install --reinstall gdm3 ubuntu-desktop gnome-shell
sudo systemctl reboot

After reinstalling those packages and rebooting, try logging in again.

Reinstall NVIDIA Driver

If your system is equipped with NVIDIA graphics, a recent update might be causing the login issues. (Usually, NVIDIA driver issues will prevent the login screen from loading at all; however, it's still worth reinstalling if you are unable to log in after the above steps.) Refer to the table below to determine if your system contains NVIDIA graphics:

To remove the NVIDIA driver, run the following:

sudo apt purge ~nnvidia
sudo apt autoremove
sudo apt clean

After the NVIDIA driver has been removed, add it back using the following commands:

sudo apt update
sudo apt full-upgrade
sudo apt install system76-driver-nvidia

After the installation has completed, type sudo systemctl reboot and try logging in again.

 

 参考链接：

Black Screen Or Login Issues (Ubuntu) - System76 Support