error running - [ERROR] Build Failed (Missing plugins directory)

i have a problem when i'm running my application. i make a beginner map application. and the wrong is [ERROR] Build Failed (Missing plugins directory). this is my code

var win = Titanium.UI.currentWindow;

var mapview = Titanium.Map.createView({ mapType: Titanium.Map.STANDARD_TYPE, region: {latitude:33.74511, longitude:-84.38993, latitudeDelta:0.01, longitudeDelta:0.01}, animate:true, regionFit:true, userLocation:true //annotations:[mountainView] });

win.add(mapview);

win.open();