I just had this problem with my shredder. I think the problem started with a bin that was full. Running the shredder in reverse resulted in shredded paper being pulled up into the slot used to feed paper into the shredder. Some of this shredded paper was blocking the little plastic tab that activates the switch when paper is inserted, so the shredder would no longer start when paper was inserted. I emptied the bin and removed the shredded paper from the feed slot, being careful not to break the plastic "sensor" while removing the paper from under it. The shredder works fine now.