key problem

[BMWCCA1]

Can't. Keep the real key's nearby. Or put up the money to buy a "real" key from BMW. The immobilizer system is capable of storing up to ten different key codes but the keys must come from BMW. Once you've used all ten, you need a complete new lock system.

(Edit: this was post #2 in this thread)

[paulcart121]

ok ive a spare key that opens the doors turns ignition on but wont start the car
e34 1995 520i
if i start the car with the other key and switch off then put spare straight in car will start
so it must have a chip in one key and not the other so how do i by pass this ??:) :)