PURPOSE: To prevent postal matter from being handed over to the main transport mechanism side in an inclined attitude by judging a horizontal condition when a plurality of sensors are actuated simultaneously, and in otherwise case, prohibiting a shutter mechanism from making the opening operation.

CONSTITUTION: Sensors 61, 62 are furnished to sense postal matter on/in an aux. transport path 22, and a horizontal attitude judging means judges that the postal matter is in horizontal attitude when any plurality of such sensors 61, 62 sense the postal matter in place simultaneously. In otherwise case, a buzzer is actuated. Therein operator corrects the attitude of the postal matter or draws it out and re-feeds afterward. A shutter mechanism 70 (72, 73) makes the opening operation under the conditions that the treatment of the failed postal matter is finished and that postal matter in the path 22 is confirmed being in the horizontal attitude, so that the postal matter is prevented from being handed over to the main transport mechanism 28 while it remains inclining.