先附上npm官方地址：https://www.npmjs.com/
1.报错npm ERR! request to https://registry.npmjs.org/@react-pdf%2frenderer failed, reason: getaddrinfo EAI_AGAIN registry.npmjs.org
解决方案：npm config set proxy http://server:port
然后npm login
2.报错npm ERR! code E409 npm ERR! 409 Conflict - PUT https://mirrors.cloud.tencent.com/npm/-/user/org.couchdb.user:bingxinke - user registration disabled
解决方案参阅：（https://huaweicloud.csdn.net/639fea60dacf622b8df8fe73.html?spm=1001.2101.3001.6661.1&utm_medium=distribute.pc_relevant_t0.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7Eactivity-1-123495661-blog-132341982.235%5Ev38%5Epc_relevant_sort&depth_1-utm_source=distribute.pc_relevant_t0.none-task-blog-2%7Edefault%7EBlogCommendFromBaidu%7Eactivity-1-123495661-blog-132341982.235%5Ev38%5Epc_relevant_sort&utm_relevant_index=1）3.报错
npm ERR! code E404
npm ERR! 404 Not Found - PUT https://www.npmjs.com/-/user/org.couchdb.user:wscfan
解决方案：
①、查看源，看是否是官方的镜像：npm config get registry
②、如果不是官方镜像，设置成官方镜像：npm config set registry https://registry.npmjs.org
【我宣布这个是最方便的，类似的淘宝镜像崩溃、页面无法访问的情况都可以直接改回官方先，后续需要改成淘宝镜像，再使用下方第五种情况的命令】
4.npm login或者npm adduser都报错
解决方案：npm config set registry https://registry.npmjs.org
5.报错request to https://registry.npm.taobao.org/core-js failed, reason: getaddrinfo ENOTFOUND server
（镜像出问题）
解决方案：打开cmd，按照顺序输入执行命令：
①、先执行命令：
npm config set proxy null
npm config set https-proxy null
②、再执行： npm config set registry http://registry.cnpmjs.org/
③、最后执行：npm install -g cnpm --registry=https://registry.npm.taobao.org