Pontiac Repair: duplicate keys, duplicate keys, security light

Question
when I put in my car key (duplicate,not gm)it starts up ,then cuts off and security light comes on..is there anyway to re-set the ignition to accept this key?

Answer
Hey Earl:

it depends of what model and year this is they all have differnt sysytems for the theft option. but thye work basically the same way. when ever key you got made make sure it looks like the original. if there are any marking on the original key like "pk3" or a "+" stamped in nthe metal make sure the key yiu had made has the same stamping. then do this use the origianl key that works and start the car/van then turn the key off and take the key out and withing 10mseconds insert the new key and start the car again it should run if it has the right style key and if the car/van didn't have more the 4 keys learned to it already. that should do it for you if not then I would get a factory key, I know they are expensive but at least they work. good luck :)