When i try using it, nothing happens. i can...

Remove the work bowl, blades, etc from off the base.
Plug the processor in and press the ON pedal down.
Use a pen to press in the rubber button on top of the base - you should hear a sound.
Now reassemble the bowl - lock the bowl in so that the handle faces front; insert blade of choice; place the tab under the feed tube of lid slightly left of center of the work bowl handle and slide the lid counter-clockwise until it clicks into place; insert pusher and make sure it locks into place.
You should be good to go again.