A paper shredder with counter-rotating shredder blades coupled to a shredder motor, including a paper tray having a floor and being shaped to receive paper. The floor has an offset slot therein adjacent to the counter-rotating shredder blades. The engagement wheels partly protrude through floor, adjacent to the offset slot. The engagement wheels frictionally engage paper and turn towards the offset slot to force paper into the shredder blades. Also, a dentate catch disposed in each corner of the paper tray temporarily holds an affixment while a sheet of paper held by the affixment is being frictionally engaged by the engagement wheels to enter the slot for comminution. A PAPER FULL sensor, a DOOR OPEN sensor, an OVERLOAD sensor, an OVERHEAT sensor, a paper-in-tray sensor, a paper-at-entry sensor, a SAFETY LOCK sensor, and a cover door open/closed sensor are provided, as are AUTO and MANUAL modes of operation.