How to fix Error: HTTP 407 Proxy Authentication Required in Node.js

What this error means

The HTTP 407 Proxy Authentication Required error indicates that your Node.js application is attempting to make an HTTP/HTTPS request through a corporate or network proxy server, but the proxy requires authentication credentials that weren't provided or were invalid. Unlike a 401 Unauthorized error (which comes from the destination server), a 407 response comes from the intermediate proxy server itself. The proxy sits between your application and the internet, and it won't forward your request until you prove you're authorized to use it. This is extremely common in corporate environments where all internet traffic must pass through authenticated proxy servers for security, monitoring, or policy enforcement purposes. The proxy server sends back a 407 status code along with a Proxy-Authenticate header that specifies which authentication methods it supports (Basic, Digest, NTLM, or custom schemes).

Typical symptoms

• npm install fails with "407 Proxy Authentication Required" or "EPROXYAUTH" error
• HTTP requests in Node.js applications timeout or fail with 407 status code
• Package managers (npm, yarn, pnpm) cannot download dependencies
• Node.js fetch() or http.request() calls fail when accessing external URLs
• Error occurs only in corporate network environments, works fine at home or on mobile hotspot
• Git operations fail with proxy authentication errors
• Docker pulls and other tools fail with similar proxy authentication issues

Common causes

1. Proxy credentials (username/password) not configured in npm configuration or environment variables
2. Incorrect username or password stored in .npmrc or system credentials
3. Special characters in password not properly URL-encoded in proxy configuration
4. Proxy authentication method (NTLM, Kerberos) not supported by Node.js or npm natively
5. Cached or outdated credentials stored in Windows Credential Manager or system keychain
6. HTTP_PROXY and HTTPS_PROXY environment variables not set or missing credentials
7. Corporate proxy settings changed (new password, different proxy server)
8. Node.js application not configured to use system proxy settings
9. Proxy server requires additional authentication headers beyond basic credentials

How to fix "Error: HTTP 407 Proxy Authentication Required"

npm config set proxy http://username:password@proxy.company.com:8080
npm config set https-proxy http://username:password@proxy.company.com:8080

npm config set proxy http://john%40doe:P%40ssw0rd%21@proxy.company.com:8080

const encoded = encodeURIComponent('P@ssw0rd!');
console.log(encoded); // P%40ssw0rd%21

export HTTP_PROXY=http://username:password@proxy.company.com:8080
export HTTPS_PROXY=http://username:password@proxy.company.com:8080
export NO_PROXY=localhost,127.0.0.1,.company.com
export NODE_USE_ENV_PROXY=1

set HTTP_PROXY=http://username:password@proxy.company.com:8080
set HTTPS_PROXY=http://username:password@proxy.company.com:8080
set NO_PROXY=localhost,127.0.0.1
set NODE_USE_ENV_PROXY=1

$env:HTTP_PROXY="http://username:password@proxy.company.com:8080"
$env:HTTPS_PROXY="http://username:password@proxy.company.com:8080"
$env:NO_PROXY="localhost,127.0.0.1"
$env:NODE_USE_ENV_PROXY="1"

proxy=http://username:password@proxy.company.com:8080
https-proxy=http://username:password@proxy.company.com:8080
strict-ssl=true

.npmrc
proxy=http://${PROXY_USER}:${PROXY_PASS}@proxy.company.com:8080
https-proxy=http://${PROXY_USER}:${PROXY_PASS}@proxy.company.com:8080

export PROXY_USER=your-username
export PROXY_PASS=your-password

// Enable environment proxy support
process.env.NODE_USE_ENV_PROXY = '1';

// fetch() will automatically use HTTP_PROXY/HTTPS_PROXY
const response = await fetch('https://api.example.com/data');

npm install proxy-agent

import { ProxyAgent } from 'proxy-agent';

const agent = new ProxyAgent({
  getProxyForUrl: () => 'http://username:password@proxy.company.com:8080'
});

const options = {
  hostname: 'api.example.com',
  path: '/data',
  agent: agent
};

https.request(options, (res) => {
  // Handle response
});

npm install axios

import axios from 'axios';

const response = await axios.get('https://api.example.com/data', {
  proxy: {
    protocol: 'http',
    host: 'proxy.company.com',
    port: 8080,
    auth: {
      username: 'your-username',
      password: 'your-password'
    }
  }
});

npm config get proxy
npm config get https-proxy

npm ping
# or
npm install express --verbose

Advanced notes

# Configure CNTLM with your credentials
   cntlm -H -u username -d DOMAIN
   # Then point npm to localhost
   npm config set proxy http://localhost:3128

pip install px-proxy
   px --proxy=proxy.company.com:8080
   npm config set proxy http://localhost:3128

import 'dotenv/config';
  const proxyUrl = `http://${process.env.PROXY_USER}:${process.env.PROXY_PASS}@proxy.company.com:8080`;

npm config set strict-ssl false
# or
export NODE_TLS_REJECT_UNAUTHORIZED=0

npm install pac-proxy-agent

import { PacProxyAgent } from 'pac-proxy-agent';
const agent = new PacProxyAgent('http://proxy.company.com/proxy.pac');

Frequently asked questions

What does "407" mean?

js application is attempting to make an HTTP/HTTPS request through a corporate or network proxy server, but the proxy requires authentication credentials that weren't provided or were invalid. Unlike a 401 Unauthorized error (which comes from the destination server), a 407 response comes from the intermediate proxy server itself. The proxy sits between your application and the internet, and it won't forward your request until you prove you're authorized to use it.

How do I fix "407"?

This error occurs when your Node.js application or npm tries to connect through a proxy server that requires authentication credentials. The request is rejected because no valid username and password were provided to the proxy.

What causes "407"?

Proxy credentials (username/password) not configured in npm configuration or environment variables Incorrect username or password stored in .npmrc or system credentials Special characters in password not properly URL-encoded in proxy configuration

Is the "407" error serious?

It is a medium-severity error — more of a blocker than a risk. The steps above resolve it.

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Official resources & further reading

• 📚Node.js Official Documentation
• 📖
  Node.js HTTP Documentation(Official Docs)
• 📖
  MDN: 407 Proxy Authentication Required(Official Docs)
• 🐙
  npm GitHub: npm install 407 Proxy Authentication Required(GitHub)
• 📝
  Kinsta: How To Fix HTTP Error 407 Proxy Authentication Required