npm install 报错 ECONNREFUSED

 在window环境下，使用npm install 命令安装任何框架，都会报如下的错误 

16 error code ECONNREFUSED
17 error errno ECONNREFUSED
18 error FetchError: request to http://localhost:4873/vue failed, reason: connect ECONNREFUSED 127.0.0.1:4873
18 error     at ClientRequest.req.on.err (C:\Program Files\nodejs\node_modules\npm\node_modules\pacote\node_modules\make-fetch-happen\node_modules\node-fetch-npm\src\index.js:68:14)
18 error     at emitOne (events.js:116:13)
18 error     at ClientRequest.emit (events.js:211:7)
18 error     at Socket.socketErrorListener (_http_client.js:387:9)
18 error     at emitOne (events.js:116:13)
18 error     at Socket.emit (events.js:211:7)
18 error     at emitErrorNT (internal/streams/destroy.js:64:8)
18 error     at _combinedTickCallback (internal/process/next_tick.js:138:11)
18 error     at process._tickCallback (internal/process/next_tick.js:180:9)
18 error  { FetchError: request to http://localhost:4873/vue failed, reason: connect ECONNREFUSED 127.0.0.1:4873

它总是首先访问localhost：4873，这里肯定是有问题的，因为本地根本没有开启这个端口，

是不是开了什么代理呢，使用npm config get proxy,发现结果为null

最后一番折腾发现原因.npmrc有问题

registry=http://localhost:4873/   #comment 
ca=null

把它注释掉，再执行安装就可以了