Air conditioning smell

Check to see if the evaporator drain is clogged. If the water is not allowed to drain, it can mold and have a bad smell. There is a filter like pad that goes in front of the evaporator that can get bad smells in them.
I know they make odor neutralizers to be sprayed in the inlet that may cancel the odor.
Good luck

It's probably mildew in the evap core, not uncommon. If you can, check the drain hoses, make sure they're clear and hooked up, I'm not sure how they run in the Windstar, they're usually under the carpet towards the firewalll behind the glovebox, again on your vehicle, I'm not sure, also you could look underneath the vehicle on a hot muggy day, water should be coming out of the hoses, don't confuse with the water dripping off the a c plumbing under the hood. There is a procedure to spray some type of disinfectant up into the evap core, may involve removing the blower motor, not 100% sure how to do it on yopur car, call the dealer, they can give you a heads-up on the whole deal. Sorry there mikey, you're post wasn't up when I first looked.