Laravel Mix的又一个坑：系统找不到指定的路径。

新安装的Laravel，按照官方教程试图安装Mix，使用默认的package.json在项目根目录运行以下命令（package.json是node的依赖文件，就像composer.json是composer的依赖文件是一个道理。

npm install

按照成功，然后运行

// Run all Mix tasks...
npm run dev

// Run all Mix tasks and minify output...
npm run production

报错
>系统找不到指定的路径。

E:\laragon\www\100>cnpm run dev

> @ dev E:\laragon\www\100
> npm run development


> @ development E:\laragon\www\100
> cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.config.js

系统找不到指定的路径。
events.js:183
      throw er; // Unhandled 'error' event
      ^

Error: spawn node_modules\webpack\bin\webpack.js ENOENT
    at notFoundError (E:\laragon\www\100\node_modules\_cross-spawn@5.1.0@cross-spawn\lib\enoent.js:11:11)
    at verifyENOENT (E:\laragon\www\100\node_modules\_cross-spawn@5.1.0@cross-spawn\lib\enoent.js:46:16)
    at ChildProcess.cp.emit (E:\laragon\www\100\node_modules\_cross-spawn@5.1.0@cross-spawn\lib\enoent.js:33:19)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:198:12)
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! @ development: `cross-env NODE_ENV=development node_modules/webpack/bin/webpack.js --progress --hide-modules --config=node_modules/laravel-mix/setup/webpack.
config.js`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the @ development script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\DVY\AppData\Roaming\npm-cache\_logs\2017-12-06T20_01_45_975Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! @ dev: `npm run development`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the @ dev script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\DVY\AppData\Roaming\npm-cache\_logs\2017-12-06T20_01_46_267Z-debug.log

E:\laragon\www\100>

最后到指定目录一看，竟然没有要的那个webpack.js，Webpack竟然是空的，任凭我怎么运行npm install，虽然都安装了，但是还是不行，最后没重新安装webpack

npm install webpack --save

OK,搞定，看来提示的没错，就是系统找不到文件，因为文件不存在，网上查了半天，多数是解释路径不对。

如果真还不能解决，删除node_modules目录，重新npm install