After being brought in out of the rain, and allowed to
thoroughly dry off, did it even try to start?
It may be something as simple as water in the fuel tank,
in which case, it should be drained and fresh fuel put in.
Also, take off the air cleaner and spray a little
carb. cleaner into the carburator and try to start it.

C'mon now, who really did leave it out in the rain? LOL. I work at a dealership and we hear this one all the time. Usually it is the kid or brudder in law.

OK ihave changed the fuel, changed the air filter, and sprayed carb cleaner in carb. It has tried to start a couple of times (Which is an improvement) but it still wont start...any other suggestions?

What model mower/motor?

You will more than likely have to empty the float bowl. Located under the carb and secured by a 1/2 nut. Just drop the bowl empty the fuel/water mixture and try a shot of carb cleaner again...