plum7500, in the log you just reported, the relevant lines are these:
[+0.03s] DEBUG: Registering seat with bus path /org/freedesktop/DisplayManager/Seat0
[+1.62s] DEBUG: Process 1470 exited with return value 127
[+1.62s] DEBUG: X server stopped
What means the X Window System Server wasn't unable to register a seat for the LightDM X Display Manager; due to a malfunction in this last one.
plum7500, in the log you just reported, the relevant lines are these:
[+0.03s] DEBUG: Registering seat with bus path /org/freedeskto p/DisplayManage r/Seat0
[+1.62s] DEBUG: Process 1470 exited with return value 127
[+1.62s] DEBUG: X server stopped
What means the X Window System Server wasn't unable to register a seat for the LightDM X Display Manager; due to a malfunction in this last one.