How did you ‘reset the settings’? Your xfce settings are stored in ‘~/.config/xfce/’. You could logout from xfce, then login in tty (crtl+alt+F2) and rename the ‘~/.config/xfce4/’-folder. (rename not delete for having a backup 
)
At next login to xfce, xfce should automatic load default settings-files from ‘/usr/share/xfce4/’ and create a new settings folder in ~/.config/.
For a less rowhammer methode you can search through the xfce config files in ‘~/.config/xfce4/’.
Sadly I cant tell you which config file exacly causes your problem. 