title: npm install error in angular2
body: <p>I am a begginer in angular2
  when i type <code>npm install</code> i got these errors:</p>
  
  <pre><code>npm WARN optional Skipping failed optional dependency /chokidar/fsevents:
  npm WARN notsup Not compatible with your operating system or architecture: fsevents@1.0.14
  npm ERR! Windows_NT 10.0.10586
  npm ERR! argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "install"
  npm ERR! node v6.3.0
  npm ERR! npm  v3.10.3
  npm ERR! file C:\Users\SIDAHMED\AppData\Roaming\npm-cache\chalk\1.1.3\package\package.json
  npm ERR! code EJSONPARSE
  
  npm ERR! Failed to parse json
  npm ERR! Unexpected token '\u0000' at 1:1
  npm ERR!
  npm ERR! ^
  npm ERR! File: C:\Users\SIDAHMED\AppData\Roaming\npm-cache\chalk\1.1.3\package\package.json
  npm ERR! Failed to parse package.json data.
  npm ERR! package.json must be actual JSON, not just JavaScript.
  npm ERR!
  npm ERR! This is not a bug in npm.
  npm ERR! Tell the package author to fix their package.json file. JSON.parse
  
  npm ERR! Please include the following file with any support request:
  npm ERR!     C:\Users\SIDAHMED\Documents\angular2\npm-debug.log
  </code></pre>
  
  <p>package.json file:</p>
  
  <pre><code>{
    "name": "ng2-test",
    "version": "1.0.0",
    "scripts": {
      "start": "concurrent \"npm run tsc:w\" \"npm run lite\" ",    
      "tsc": "tsc",
      "tsc:w": "tsc -w",
      "lite": "lite-server",
      "typings": "typings",
      "postinstall": "typings install" 
    },
    "license": "ISC",
    "dependencies": {
      "angular2": "2.0.0-beta.7",
      "systemjs": "0.19.22",
      "es6-promise": "^3.0.2",
      "es6-shim": "^0.33.3",
      "reflect-metadata": "0.1.2",
      "rxjs": "5.0.0-beta.2",
      "zone.js": "0.5.15"
    },
    "devDependencies": {
      "concurrently": "^2.0.0",
      "lite-server": "^2.1.0",
      "typescript": "^1.7.5",
      "typings":"^0.6.8"
    }
  }
  </code></pre>
  
  <p>i tried <code>npm install angular2@2.0.0-alpha.32</code> and when i type <code>npm start</code>
  i have these error messages:</p>
  
  <pre><code>&gt; ng2-test@1.0.0 start C:\Users\SIDAHMED\Documents\angular2
  &gt; concurrent "npm run tsc:w" "npm run lite"
  
  'concurrent' n’est pas reconnu en tant que commande interne
  ou externe, un programme exécutable ou un fichier de commandes.
  
  npm ERR! Windows_NT 10.0.10586
  npm ERR! argv "C:\\Program Files\\nodejs\\node.exe" "C:\\Program Files\\nodejs\\node_modules\\npm\\bin\\npm-cli.js" "start"
  npm ERR! node v6.3.0
  npm ERR! npm  v3.10.3
  npm ERR! code ELIFECYCLE
  npm ERR! ng2-test@1.0.0 start: `concurrent "npm run tsc:w" "npm run lite" `
  npm ERR! Exit status 1
  npm ERR!
  npm ERR! Failed at the ng2-test@1.0.0 start script 'concurrent "npm run tsc:w" "npm run lite" '.
  npm ERR! Make sure you have the latest version of node.js and npm installed.
  npm ERR! If you do, this is most likely a problem with the ng2-test package,
  npm ERR! not with npm itself.
  npm ERR! Tell the author that this fails on your system:
  npm ERR!     concurrent "npm run tsc:w" "npm run lite"
  npm ERR! You can get information on how to open an issue for this project with:
  npm ERR!     npm bugs ng2-test
  npm ERR! Or if that isn't available, you can get their info via:
  npm ERR!     npm owner ls ng2-test
  npm ERR! There is likely additional logging output above.
  
  npm ERR! Please include the following file with any support request:
  npm ERR!     C:\Users\SIDAHMED\Documents\angular2\npm-debug.log
  </code></pre>