I have all pieces locked into place and it will

First thing to do is check your base to make sure it's not something wrong there. If you take everything off the base and look on top, either in the 6 or 12 o' clock position there will be a black button set into the base slightly. You want to find a ball point pen, and with the base plugged in, press and hold that button while turning on the unit.

If that works, you want to go through each piece one at a time. First w/ the work bowl, and notice there is a plastic rod w/ a spring at the bottom set into on side of the work bowl. Make sure that is lined up over the black button. Then in the cover, usually on the back of the feed tube, there is a lever within the clear plastic, that should line up over the rod in the work bowl. Finally, you must add the pusher/sleeve portion at the very last, or else it all won't engage right and it won't work. Just make sure the tabs on the large pusher are locked into the cover last, and it all engages so that the spring in the work bowl is depressed. The processor won't work until all the pieces are in the exact place and put on one at a time (I can't stress that enough because these processors are very exact when it comes to that, some kind of safety mechanism).

If all else fails, call customer service at 800-726-0190, they can walk you through those steps if I haven't been clear enough. :)