从Xubuntu 16.04 LTS升级至17.10后出现登录循环问题

安全阿岳

2026-5-19

Hey there, I’ve dealt with similar login loop headaches after jumping between Ubuntu-based releases, so I feel your pain here. Let’s walk through some troubleshooting steps that might fix this for you:

Check filesystem permissions on your home directory
Sometimes upgrades mess up ownership. When you get to the login screen, press Ctrl+Alt+F3 to drop into a TTY. Log in with your credentials, then run:
sudo chown -R $USER:$USER $HOME
This resets ownership of all files in your home folder back to your user account. Reboot and try logging in again.
Verify lightdm configuration isn’t corrupted
Reinstalling lightdm might not reset its config. Try purging it completely first, then reinstall:
sudo apt purge lightdm
sudo apt autoremove
sudo apt install lightdm
When prompted, make sure to select lightdm as your default display manager.
Fix broken packages or upgrade leftovers
Partial upgrades are a common culprit here. Run these commands in TTY to resolve broken packages and finish any pending upgrades:
sudo apt update
sudo apt upgrade --fix-missing
sudo apt dist-upgrade
sudo apt autoremove && sudo apt clean
Test with a new user account
Create a temporary user to rule out profile-specific corruption:
sudo adduser testuser
sudo usermod -aG sudo testuser
Reboot and try logging in as testuser. If it works, your original user profile has corrupted config files—you can migrate your data to the new account or start by deleting ~/.config/xfce4 to reset Xfce settings.
Resolve graphic driver conflicts
Xubuntu 17.10 uses a newer Xorg server than 16.04, which might clash with old proprietary drivers. In TTY, remove any third-party drivers first:
sudo apt purge nvidia* (replace nvidia* with your driver package if you use AMD/Intel)
Then install the open-source alternative:
sudo apt install xserver-xorg-video-intel (for Intel GPUs) or xserver-xorg-video-amdgpu (for AMD GPUs)
Reboot and test the login again.