I put a new pcm in my 02 cavilier and it will not start When you put the stock pcm back in the car starts How do you get the car to start with the new pcm?

I put a new pcm in my 02 cavilier and it will not start When you put the stock pcm back in the car starts How do you get the car to start with the new pcm?
find a parts house or dealer that can flash the new PCM, you will need the Vin.# year make and modle.