当我在代理设置中没有http/http前缀时，即使代理主机和端口是正确的值，npm也会失败。只有在添加协议前缀后，它才能正常工作。

要设置http代理，请设置-g标志:

Sudo NPM配置代理http://proxy_host:port -g

对于https代理，再次确保设置了-g标志:

Sudo NPM配置http -proxy http://proxy_host:port -g

对于这个问题，上面有很多答案，但没有一个对我有用。他们都提到要添加http://前缀。所以我也加了进去。都失败了。

它终于工作后，我不小心删除了http://前缀。最终配置如下:

npm config set registry http://registry.npmjs.org/
npm config set http-proxy ip:port
npm config set https-proxy ip:port
npm config set proxy ip:port
npm set strict-ssl false

我不知道这背后的逻辑，但它奏效了。如果以上答案都不适合你，也许你可以试试这种方法。希望这个对你有用。

Windows系统

尝试删除代理和注册表设置(如果已经设置)，并通过命令行设置环境变量

SET HTTP_PROXY=http://username:password@domain:port
SET HTTPS_PROXY=http://username:password@domain:port

然后尝试运行NPM install。这样，你就不用在.npmrc中设置代理了，但是对于那个会话，它是可以工作的。

npm config set proxy <http://...>:<port_number>
npm config set registry http://registry.npmjs.org/

这解决了我的问题。

在curl的页面上有关于SSL和证书问题的很好的信息。 我的大部分答案都是基于那里的信息。

使用strict-ssl false是不好的做法，可能会产生问题。我们可以做的是添加由“中间人”证书注入的证书。

如何在Windows上解决这个问题:

Download the CA Certificates from curl based on Mozilla's CA bundle. You can also use curl's "firefox-db2pem.sh" shellscript to convert your local Firefox database. Go to a webpage using https, for example Stackoverflow in Chrome or Internet Explorer Click the lock icon, click View certificates or "Valid" in Chrome Navigate to the Certification path. The top certificate, or the root certificate is the one we want to extract. Click that certificate and then "view certificate" Click the second tab, "Details". Click "Copy to file". Pick the DER format and make note of where you save the file. Pick a suitable filename, like rootcert.cer If you have Git installed you will have openssl.exe. Otherwise, install git for windows at this stage. Most likely the openssl executable will be at C:\Program Files\git\usr\bin\openssl.exe. We will use openssl to convert the file to the PEM format we need for NPM to understand it. Convert the file you saved in step 5 by using this command: openssl x509 -inform DES -in **rootcert**.cer -out outcert.pem -text where rootcert is the filename of the certificate you saved in step 5. Open the outcert.pem in a text-editor smart enough to understand line-endings, so not notepad. Find -----BEGIN CERTIFICATE----- lots of characters -----END CERTIFICATE----- and copy all text between them and also including the BEGIN / END lines Now we will paste that content to the end of the CA Cert bundle made in step 1. So open the cacert.pem in your advanced texteditor. Go to the end of the file and paste the content from previous step to the end of file. (Preserve the empty line below what you just pasted) Copy the saved cabundle.pem to a suitable place. Eg your %userprofile% or ~. Make note of the location of the file. Now we will tell npm/yarn to use the new bundle. In a commandline, write npm config set cafile **C:\Users\username\cacert.pem** where C:\Users\username\cacert.pem is the path from step 10. Optionally: turn on strict-ssl again, npm config set strict-ssl true

唷!我们成功了!现在npm可以理解如何连接了。额外的好处是，您可以告诉curl使用相同的cabundle。pem，它也能理解HTTPs。