2002 impala wont start?

i have a 3.8 impala and i just changed the switch of the ignition now it wont start i put the old one back on and it wont start either i got it to start straight from the starter but it shuts off. what can this be and how can i fix it also everything turns on just dosent crank at all2002 impala wont start?
yea i have heard of this before with some of the new cars the computer thinks you are trying to steal it so it shuts down the car

also you might have blow a fuse some where or crossed wires with something just a guess with out really looking at it2002 impala wont start?
call the dealer, you might have flashed your computer ( security )

they will have to program it

hide my myspace friends

what is the name of