That reset thing in the trunk is the most likely.
On the way out there chance you have two fords make sure you are using the right key. Sunday I went to an autocross and unload my 99 GT off the trailer, go through tech, and park it. Comes time to go to grid and the damn engine cranks over but won't start. I raise the hood and look around then get out the fuse and relay chart to mull over the possibilities. I'm walking aroung the car, stick my hand in my pocket, and feel my Mustang key. I look in the car and see my wad of keys my truck key is on hanging in the ignition. It turns out my 2003 F150 key will turn the ignition lock on my 99 Mustang but wrong transponder = no start.