immobiliser wont switch off after new car battery fitted?

the key needs programmed, the way to do it is, close the car. Insert the key into drivers door pressing an holding the button with the lock symbol. Turn the key as if locking, still holding the lock button down. Hold in position for 3secs. Turn back to the centre position an pull the key out-still holding the key button. Once the key is out release the lock button. IF THIS DOESNT WORK FIRST TIME DONT GIVE UP REPEAT THE ABOVE

supernova
February 2007