npm下载权限不足问题解决

windows系统下使用node.js在使用npm安装tyarn时报错的解决方法，

下列方法适用大部分npm下载权限不足问题

npm ERR! code EPERM
npm ERR! syscall open
npm ERR! path C:\Program Files\nodejs\npm_cache\_cacache\tmp\2f17465b
npm ERR! errno -4048
npm ERR! Error: EPERM: operation not permitted, open 'C:\Program Files\nodejs\npm_cache\_cacache\tmp\2f
17465b'
npm ERR!  [OperationalError: EPERM: operation not permitted, open 'C:\Program Files\nodejs\npm_cache\_c
acache\tmp\2f17465b'] {
npm ERR!   cause: [Error: EPERM: operation not permitted, open 'C:\Program Files\nodejs\npm_cache\_caca
che\tmp\2f17465b'] {
npm ERR!     errno: -4048,
npm ERR!     code: 'EPERM',
npm ERR!     syscall: 'open',
npm ERR!     path: 'C:\\Program Files\\nodejs\\npm_cache\\_cacache\\tmp\\2f17465b'
npm ERR!   },
npm ERR!   isOperational: true,
npm ERR!   stack: "Error: EPERM: operation not permitted, open 'C:\\Program Files\\nodejs\\npm_cache\\_
cacache\\tmp\\2f17465b'",
npm ERR!   errno: -4048,
npm ERR!   code: 'EPERM',
npm ERR!   syscall: 'open',
npm ERR!   path: 'C:\\Program Files\\nodejs\\npm_cache\\_cacache\\tmp\\2f17465b'
npm ERR! }
npm ERR!
npm ERR! The operation was rejected by your operating system.
npm ERR! It's possible that the file was already in use (by a text editor or antivirus),
npm ERR! or that you lack permissions to access it.
npm ERR!
npm ERR! If you believe this might be a permissions issue, please double-check the
npm ERR! permissions of the file and its containing directories, or try running
npm ERR! the command again as root/Administrator.

提供几种如下解决方案

1. 使用win+x,选择命令提示符（管理员），在里面运行命令就好了。

2. 如果自己本身就是管理员权限，因而无用，最后症结是缓存问题导致

需要删除npmrc文件。

强调：不是nodejs安装目录npm模块下的那个npmrc文件

而是在C:\Users\{账户}\下的.npmrc文件..

3. 当然也有说用命令清除缓存的，我自己试了下没成功，上面删除文件来的更加直接彻底，关键是见效。

直接用命令清理就行，控制台输入：

npm cache clean --force