Ford Repair: Vehicle will not start nor will the OBD comp diag work., ford f 150, spark plug wire

Question
I have a 1997 ford F 150 small cab 2wd.  It's a six cylinder with approx. 70,000 miles.  I parked the car one day and the next I try to start it and no ignition.  The starter turns the engine but no combustion.  Here is what ive come up with.  I disconnected the fuel live by the fuel filter and turned the ignition and fuel comes out so i know the pump is working.  I go to autozone and got a OBD autoscanner and tried to test it and it gives me a communications error message.  I have checked every fuse in the vehicle and the only one out was the cig lighter.  I replaced it plug the diag machine back in and turned the ignition on and i get the same error.  I have also checked inside the distributor and no water was in there.  I tried carb cleaner in the throddle body and nothing.  I am not receiving any spark and the diag test wont run so i am stumbed.  Ohh and i tried the autoscanner on another vehicle and it works well so i know its not the scanner.  I also took the spark plug wire out and the spark plug and put a screw driver very close to it had someone try to start it and there was no sparks thats how i know that im not receiving any spark.  I think the computer fried but im not an expert.  plus it wouldn't make since that i turned it off and everything ran fine and next day the computer is mysteriously dead.

Answer
check fusible links under plastic cover rear of engine on passenger side-make sure battery cables are clean especially ground and wire coming off of post-check relays make sure there are no ants in them in engine compartment relay box if they get in them they will short out contacts or force them open and you won't have communication-happened just yesterday on dodge stratus at the shop-third vehicle this year.