Hi and welcome to the club.
The key isn't programmed, its just a chip resistor embedded in the key. If your security light stays on then iits time to look into the key & cylinder; if its not on your problem is elsewhere. Possibly the solenoid, ignitions switch, or eec relay.
You can easily find the values posted on the net for the key resistances.(I'm not sure if we're allowed to post them here so I didn't). Measure the ohms across the pellet in the key; It should fall into one of the valid ranges: if not replace the key. Next disconnect the two wires comming down the streering column, typically white wire that may be in an orange sleeve, with the key in - backprobe the those wires going up the steering column and see if you get the same resistance reading as the key. If not replace the lock cylinder.
98 SSEi 111,222 miles.
Intense PCM, LS6 Valve springs, PEMS, FWI. Hawk Street Pads.