Solution - no configuration file found and no output filename configured via cli option. a configuration file could be named 'webpack.config.js' in the current directory. use --help to display the cli options.

Missing default webpack configuration webpack.config.js file

Create default webpack configuration webpack.config.js file

When you run the webpack executable, it looks for a configuration file named webapack.config.js which has the following format:

// NOTE: Config files are highly dependant
// on project structure
module.exports = {
    entry: "./entry.js",
    output: {
        path: __dirname,
        filename: "bundle.js"
    },
    module: {
        loaders: [
            { test: /\.css$/, loader: "style!css" }
        ]
    }
};		

Webpack uses a non-default configuration file

Look for a webpack configuration file other than webapack.config.js (e.g. dev.config.js).

See the 'Steps' section above and look for a file with a similar structure. If found, invoke the webpack executable with the --config flag pointing to this non-default webpack configuration file.

Missing exports statement in the webpack configuration file

Ensure the webpack configuration file is headed by an exports statement.

The main webpack configuration file webapack.config.js must start with:

		module.exports = {
		    ...
		    ...
		 }