Angular: ng new error when I create an angular project

The problem seems to be the _ in project_name resulting in the following error:

Schematic input does not validate against the Schema: {"name":"project_name","version":"6.0.1","newProjectRoot":"projects","skipInstall":false,"linkCli":false,"skipGit":false,"commit":null}
Errors:

  Data path ".name" should match format "html-selector".

Replace _ e.g. with -.

Further readings:

• Error when creating new project with Angular-CLI 6.1.2
• Style Guide

If you are using the terminal of IntelliJ IDEA while there is a angular project already imported in the IDEA, it is the problem of the IDEA.So, open the command promt of your windows and create the project.

I did this and I was able to create the project.

Setting the working directory in IntelliJ's Karma task, to the Angular project's main directory, also fixes the problem.