Can't do PATS key relearn with autoenginuity 9.1

I'm working on a 2001 Excursion w/ 7.3 PSD. It has one key. The guy I bought it from said that he only got one key from the guy he bought it from. Super. I'd like to not pay a dealer a small fortune to reprogram it, especially since I have AE and two more transponder keys that turn in the ignition.


So I tried to do the PATS programming thing in AE, and it doesn't work. It doesn't exactly have much detail about what to do, so I'm probably doing something it doesn't expect. Here's what I'm doing:
insert working key, turn to on
Connect AE dongle to DTC and computer
Run AE, connect to vehicle, read sensors, not get codes (no engine light is on)
Go to test onboard system tab
select PATS key programming
click initiate button
select program additional key
click done button
wait for the ten minute countdown
select program additional key (again)
click done button
it fails with "key was not programmed due to system busy or refusal"


I also tried it with pulling the working key after the ten minute countdown finished, inserting the new key, turning it to run, but AE lost communication with the PCM.


Am I missing something here?