express 运行时出错

Question

express express-generator 生成的模板应用， 执行 npm run dev
package.json - >

  "scripts": {
    "start": "node ./bin/www",
    "dev": "set DEBUG=myapp:* & npm start"
  },

报错信息：
ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! myapp@0.0.0 start: node ./bin/www
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the myapp@0.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.