When Septime is being instructed to walk around the news stand, a man and woman approach the stand twice between the changing shots.
As Septime and the secretary tumble down the hill their clothes get covered with snow, but when they reach the bottom they're clean again.
During the dance rehearsal, the broken plate on the floor changes between shots.
In the chase scene when Septime drives his car into the snowbank, its on an angle, but the next shot shows a car shaped hole that is shorter than it should be and as if the car hit straight on.
When the sliding upside-down car finally comes to a stop on the frozen lake, you can clearly see that there's no one inside it, which conflicts with the close up interior shots of Monsieur Septime and the secretary.
Throughout the movie, it's obvious that the pianist in the restaurant isn't really playing the music that we hear.
When the cars is upside down going on the village road on the snow, you you can see small wheels in the roof.
Near the end, when Septime go out from the black Mercedes and go into the garden, the shadow of the boom mic is clearly visible on the yucca at the top left of the screen.