ExpressJS - throw er Unhandled error event

Question

I created expressjs application using the following commands:

express -e folderName
npm install ejs --save
npm install

When I run the appli

Answer 1

The port Node is trying to use can be already used by another program. In my case it was ntop, which I had recently installed. I had to open http://localhost:3000/ in a browser to realize it. Another way to find the process is given here.