SharedObject on AIR on Windows. Help!

The code, below, writes normally when publishing to FlashPlayer. It does not write at all when publishing to AIR (3.9).

Please tell me I'm doing something dumb!

package source

{

          import flash.display.MovieClip;

  import flash.net.SharedObject;

  public class MAIN extends MovieClip

         {

            var mySO:SharedObject = SharedObject.getLocal("myThing","/")

public function MAIN()

         {

             var thing:int = 12;

             mySO.data.sharedthing = thing;

             mySO.flush();

         }

    }

}