The door has a window weather strip attached to a slot opening and accommodated in a fastening groove (30) formed by a longitudinal bar (24) of a slot reinforcement (17). A downward bending flange (22) of a door outer panel is formed as a free standing wall (40) that is firmly connected with its lower end section (26) with the slot reinforcement. The wall together with the bar laterally limits the fastening groove. The bar is provided with a passage, which forms a groove base of the fastening groove.
