The shutter button is surrounded by a 'lock' switch. Make certain that this switch is off. If, still, no shutter fires, make sure that the self-timer switch is not half-way down. If this is not resolved, the shutter will not fire. Finally, see if the curtain is fully closed. On these old, cloth shutter bodies, sometimes the curtain tension wanes and the shutter does not complete its journey. You might, carefully, lift the mirror and, with thumb and index finger, grasp that cloth curtain and gently guide it to completion. If so, the curtain springs need to be tensioned, from the bottom. (Too difficult to go into here.) - David Lyga