"else not running executing in function(err)

I'm trying to console log whether or not my function is running successfully, or it encounters an error.

var gui = require('nw.gui'); 
var fs  = require('fs');

onload = function() {
    //console.log(gui.App.argv);
    console.log("onload() is running - from <saveFile.js>")
    var outputPath = gui.App.dataPath + "\\saves\\" + "content.txt";
    var content = "hello world";
    fs.writeFileSync(outputPath, JSON.stringify(content), "utf8", function(err) {
        if(err) {
            console.log(err);
        }
        else{ 

                console.log('saved in ' + outputPath);
        }
    });


};

it logs the error if encountered, but the else statement never executes.