npm ERR! code EPERM
npm ERR! syscall unlink
npm ERR! path E:\myspace\vue-element-admin\node_modules\.staging\@hapi\joi-33d00                                                                                            ac9\lib\errors.js
npm ERR! errno -4048
npm ERR! Error: EPERM: operation not permitted, unlink 'E:\myspace\vue-element-a                                                                                            dmin\node_modules\.staging\@hapi\joi-33d00ac9\lib\errors.js'
npm ERR!  [OperationalError: EPERM: operation not permitted, unlink 'E:\myspace\                                                                                            vue-element-admin\node_modules\.staging\@hapi\joi-33d00ac9\lib\errors.js'] {
npm ERR!   cause: [Error: EPERM: operation not permitted, unlink 'E:\myspace\vue                                                                                            -element-admin\node_modules\.staging\@hapi\joi-33d00ac9\lib\errors.js'] {
npm ERR!     errno: -4048,
npm ERR!     code: 'EPERM',
npm ERR!     syscall: 'unlink',
npm ERR!     path: 'E:\\myspace\\vue-element-admin\\node_modules\\.staging\\@hap                                                                                            i\\joi-33d00ac9\\lib\\errors.js'
npm ERR!   },
npm ERR!   errno: -4048,
npm ERR!   code: 'EPERM',
npm ERR!   syscall: 'unlink',
npm ERR!   path: 'E:\\myspace\\vue-element-admin\\node_modules\\.staging\\@hapi\                                                                                            \joi-33d00ac9\\lib\\errors.js',
npm ERR!   parent: 'vue-element-admin'
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 ant                                                                                            ivirus),
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 t                                                                                            he
npm ERR! permissions of the file and its containing directories, or try running
npm ERR! the command again as root/Administrator.

以管理员身份运行 powerShell , 再执行 npm install --registry=https://registry.npm.taobao.org  解决了问题

ps:

(1) 在编辑器的终端里运行命令的速度要比git bash 中流畅

(2) git bash 执行命令响应慢的解决方法：https://www.cnblogs.com/Idxy/p/4402050.html