The low-temperature longitudinal and Hall resistances of a two-dimensional electron gas are studied in the presence of a magnetic barrier created under the edge of a thin ferromagnetic film. An in-plane external magnetic field allows us to tune the barrier height within the classically transmissive regime. A theoretical model is presented that predicts the size and shape of the resistance correction for the ballistic case in the presence of a single magnetic barrier. The model that contains no adjustable parameters is in qualitative agreement with the experiment. The size of the predicted resistance correction agrees with the measurement within a factor of 2.