Comment 2 for bug 1635935

When things came to go wrongly, then its time to:
- glance at logs to know about a usefull warning/error
- clean the system: 'sudo apt-get clean' (same with autoclean & autoremove)
- when package is removed, always select 'full removal' (purge)
- search & purge orphans with gtkorphan

But mixing several DEs (gnome+xfce+...) is the worst idea really (better to do a fresh reinstall if a quick fix can't be made)