First, I've never heard of an explorer 'scout'. I think you mean 'Sport'. Anyways, your key has a microchip in it that's unique to that key, and everytime you want to stop the truck it checks for the correct key by talking to that microchip. It appears that when you used the wrong key the truck detected this and may have thought it was a theft attempt. I owned a 99 explorer with the same key system and if I remember the manual correctly, once it detects the right key it will start. So, I am not sure why it isn't starting when you use the correct key. Put the correct key in and....ohhhhhh I got it. The steering wheel lock is engaged. Put the correct key in, with your right hand jiggle the key (keep trying to turn it) and with your left hand move the steering wheel left to right. It should only move a few centimetres in each direction and then the steering wheel will all of a sudden move freely and the key will turn. This is an anti-theft device that I will admit I have forgotten about in the past (nothing more embarrassing). So simple yet almost hidden. Give that a go and you should be off to the races. For future reference, the anti-theft light blinks all the time except for when the vehicle is running. It...just does that. So, in this case the fact that it's blinking is irrelevant. Hope this helps, Good luck