LightDM returns to login screen when starting XFCE session

[mtosatti33]

Description

Environment:

• Arch Linux (fresh installation)
• VirtualBox virtual machine
• XFCE desktop environment
• LightDM with lightdm-gtk-greeter
• BIOS boot mode

Issue:
After entering the correct password in LightDM, authentication succeeds, but the XFCE session does not start. Instead, LightDM immediately returns to the login screen without displaying an authentication error.

Observations:

• Incorrect passwords are correctly rejected by LightDM.
• Correct passwords are accepted.
• No visible error message is displayed.
• XFCE is installed and available as a session.
• Xorg starts correctly.
• The user account is valid.
• Running startxfce4 manually from a TTY starts XFCE successfully.
• Replacing LightDM with GDM allows the same XFCE session to start normally.
• After switching to GDM, XFCE works without any additional configuration changes.

Troubleshooting performed:

• Verified XFCE installation.
• Verified Xorg installation.
• Verified user account permissions.
• Tested manual session startup with startxfce4.
• Replaced LightDM with GDM on the same system.

Expected behavior:
After successful authentication, LightDM should launch the XFCE desktop session.

Actual behavior:
Authentication succeeds, but LightDM returns to the login screen instead of starting XFCE.

[leigh123linux]

Have you got a static hostname?, it really screws up xorg if it changes during bootup.

[delinuxco]

@mtosatti33 try this, drop down to a terminal and reinstall lightdm from the command line (Ctr+Alt+F3), then restart lightdm using sudo systemctl restart lightdm.
I seem to be having a similar issue... https://forum.manjaro.org/t/need-help-with-live-buildiso/188350