I had the same problem this morning.
cp /usr/share/themes/Human/gtk-2.0/gtkrc /usr/share/themes/Human/gtk-2.0/gtkrc.en
fixed the problem for me.
I had the same problem this morning.
cp /usr/share/ themes/ Human/gtk- 2.0/gtkrc /usr/share/ themes/ Human/gtk- 2.0/gtkrc. en
fixed the problem for me.