| From about ten days ago, after a d-u, at the beginning and before to ask for user and password, this message appears: 
 
  Oh no! Something has gone wrong. A problem has accurred and the system can't recover.
 Please log out and try again.
 
 (emoticon included)
 Logging out and trying again brings the same message.
 
 
 However, if I run into another tty (Ctrl+Alt+F2), log in with my normal username and password and I order "startx", the system starts well. My desktop environment is Xfce.
 
 Any clue?
 
 
 Thanks for your time..
 
 
 Edit:
 I did a look into /var/log searching something interesting, and I found this:
 
       Code: 
$cat /var/log/Xorg.0.log | grep error
 (WW) warning, (EE) error, (NI) not implemented, (??) unknown.
 [    31.675] (EE) AIGLX error: dlopen of /usr/lib/x86_64-linux-gnu/dri/r600_dri.so failed (/usr/lib/x86_64-linux-gnu/dri/r600_dri.so: cannot open shared object file: No such file or directory)
 [    31.675] (EE) AIGLX error: dlopen of /usr/lib/x86_64-linux-gnu/dri/swrast_dri.so failed (/usr/lib/x86_64-linux-gnu/dri/swrast_dri.so: cannot open shared object file: No such file or directory)
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