Failed to resolve loader: less-loader

使用VSCode启动Vue项目控制台报以下错误： 

Failed to resolve loader: less-loader
You may need to install it.
Error from chokidar (C:\): Error: EBUSY: resource busy or locked, lstat 'C:\hiberfil.sys'
Error from chokidar (C:\): Error: EBUSY: resource busy or locked, lstat 'C:\pagefile.sys'
Error from chokidar (C:\): Error: EBUSY: resource busy or locked, lstat 'C:\swapfile.sys'

解决方法：安装less-loader

npm install less less-loader --save-dev