Please provide us with the following information:

OS?

Windows 7, 8 or 10. Linux (which distribution). Mac OSX (Yosemite? El Capitan?)
Mac OSX Sierra

Versions.

Please run ng --version. If there's nothing outputted, please run in a Terminal: node --version and paste the result here:

angular-cli: 1.0.0-beta.11-webpack.8
node: 6.6.0
os: darwin x64

Repro steps.

Was this an app that wasn't created using the CLI? What change did you do on your code? etc.
No, the app has been freshly created from scratch with CLI, just tried to add a new module.

The log given by the failure.

Normally this include a stack trace and some more information.

blackat:ng-navbar eugenio$ ng g module navbar
Could not start watchman; falling back to NodeWatcher for file system events.
Visit http://ember-cli.com/user-guide/#watchman for more info.
installing module
  create src/app/navbar/navbar.module.ts
installing component
  create src/app/navbar/navbar.component.css
  create src/app/navbar/navbar.component.html
  create src/app/navbar/navbar.component.spec.ts
  create src/app/navbar/navbar.component.ts
astUtils.addComponentToModule is not a function
TypeError: astUtils.addComponentToModule is not a function
    at Class.afterInstall (/Users/eugenio/Projects/Github/ng-navbar/node_modules/angular-cli/addon/ng2/blueprints/component/index.js:125:18)
    at tryCatch (/Users/eugenio/Projects/Github/ng-navbar/node_modules/rsvp/dist/lib/rsvp/-internal.js:215:12)
    at invokeCallback (/Users/eugenio/Projects/Github/ng-navbar/node_modules/rsvp/dist/lib/rsvp/-internal.js:230:13)
    at publish (/Users/eugenio/Projects/Github/ng-navbar/node_modules/rsvp/dist/lib/rsvp/-internal.js:198:7)
    at flush (/Users/eugenio/Projects/Github/ng-navbar/node_modules/rsvp/dist/lib/rsvp/asap.js:85:5)
    at _combinedTickCallback (internal/process/next_tick.js:67:7)
    at process._tickCallback (internal/process/next_tick.js:98:9)

Thanks a lot for your help 😉