Error Code 407 (HTTP 407 Proxy Authentication Required)

Meaning

HTTP Error 407 – Proxy Authentication Required is an HTTP client error status code that indicates the client must authenticate itself with a proxy server before the request can be forwarded to the destination server.

Unlike HTTP 401 Unauthorized, where authentication is required by the destination web server, 407 specifically means that a proxy server is requesting valid authentication credentials.

The proxy server returns a Proxy-Authenticate response header, and the client must resend the request with the appropriate Proxy-Authorization header.

Common Causes

1. Missing Proxy Authentication

The client is attempting to access the internet through a proxy server without providing a username and password.

2. Incorrect Username or Password

The proxy credentials are incorrect or have expired.

3. Proxy Server Requires Authentication

Many enterprise, corporate, school, and ISP proxy servers require user authentication before allowing internet access.

4. Invalid Proxy Configuration

The proxy server address or port is incorrect.

Example:

• Wrong IP address
• Incorrect hostname
• Wrong port number

5. Expired Authentication Session

The proxy login session has expired, requiring the user to authenticate again.

6. Browser Proxy Misconfiguration

The browser is configured to use a proxy that either:

• No longer exists
• Requires authentication
• Is offline

7. Application Doesn’t Support Proxy Authentication

Some applications do not send the required Proxy-Authorization header.

8. VPN or Corporate Network

Many VPNs and corporate networks route traffic through authenticated proxy servers.

9. Firewall or Gateway Policy

A firewall or secure web gateway requires authenticated proxy access before allowing outbound connections.

10. Proxy Authentication Method Not Supported

The client and proxy server use different authentication mechanisms.

Examples:

• Basic
• Digest
• NTLM
• Kerberos
• Negotiate

11. Proxy Server Configuration Errors

The proxy server may be:

• Misconfigured
• Overloaded
• Restarting
• Rejecting valid credentials

12. Cached Invalid Credentials

The browser or operating system has stored outdated proxy credentials.

How to Fix

Step 1: Verify Internet Connection

Ensure the network connection is working before troubleshooting the proxy.

Step 2: Check Proxy Settings

Windows

Settings

→ Network & Internet

→ Proxy

Verify:

• Proxy Address
• Port
• Authentication

macOS

System Settings

→ Network

→ Proxies

Verify the configured proxy information.

Step 3: Enter Correct Proxy Credentials

Provide the correct:

• Username
• Password
• Domain (if required)

Step 4: Disable Proxy (If Not Needed)

If you don’t require a proxy:

Windows

Settings

→ Network & Internet

→ Proxy

Turn Use a proxy server OFF.

Browser

Disable any manually configured proxy.

Step 5: Clear Saved Proxy Credentials

Windows:

Credential Manager

Remove old proxy credentials.

Step 6: Contact Network Administrator

If you’re on:

• Office network
• School network
• Corporate VPN

Request updated proxy credentials.

Step 7: Verify Proxy Address

Confirm:

• Hostname
• IP address
• Port

Example:

text
http://proxy.company.com:8080

Step 8: Configure Application Proxy

Ensure your application supports authenticated proxies.

Examples:

• Java
• Python
• Node.js
• .NET
• JavaScript
• cURL

Step 9: Check Authentication Method

Ensure the application supports the required authentication type.

Examples:

• Basic Authentication
• NTLM
• Kerberos
• Digest Authentication

Step 10: Test Without Proxy

Temporarily disable the proxy.

If the website opens normally, the issue is almost certainly with the proxy configuration or credentials.

Step 11: Clear Browser Cache

Cached authentication headers can sometimes cause repeated 407 errors.

Clear:

• Cache
• Cookies
• Saved passwords

Step 12: Restart Browser or Device

Restart:

• Browser
• Computer
• VPN
• Network adapter

Examples

Example 1

Error

text
HTTP Error 407
Proxy Authentication Required

Reason

No proxy credentials were provided.

Solution

Enter the correct proxy username and password.

Example 2

Error

text
407 Proxy Authentication Required

Reason

The browser attempted to connect through an authenticated corporate proxy.

Solution

Authenticate using valid company credentials.

Example 3

cURL

bash
curl: (56) Received HTTP code 407 from proxy after CONNECT

Reason

The proxy rejected the request because authentication was missing or invalid.

Solution

Provide proxy credentials.

Example:

bash
curl –proxy-user username:password https://example.com

Example 4

Java

text
java.io.IOException:
Unable to tunnel through proxy.
Proxy returns “HTTP/1.1 407 Proxy Authentication Required”

Reason

Java attempted to use a proxy without authentication.

Solution

Configure proxy authentication properties or use an authenticated ProxySelector.

Example 5

Python Requests

text
requests.exceptions.ProxyError:
407 Proxy Authentication Required

Reason

The requests library attempted to connect through an authenticated proxy without valid credentials.

Solution

Pass the correct proxy URL with authentication details.

Example 6

Axios (Node.js)

text
AxiosError:
Request failed with status code 407

Reason

The configured proxy requires authentication.

Solution

Configure Axios with the appropriate proxy credentials or authentication settings.

Example 7

Chrome Browser

text
407 Proxy Authentication Required

Reason

Chrome detected an authenticated proxy but no valid credentials were available.

Solution

Enter valid proxy credentials or disable the proxy if it is not required.

Example 8

Microsoft Edge

text
This proxy requires authentication.
HTTP ERROR 407

Reason

The proxy server denied access until authentication is completed.

Solution

Authenticate with the proxy or verify your organization’s proxy settings.

Example 9

Corporate VPN

text
407 Proxy Authentication Required

Reason

Traffic routed through the VPN requires authenticated proxy access.

Solution

Reconnect to the VPN and verify your corporate login credentials.

Example 10

Browser Developer Tools

text
Status Code: 407 Proxy Authentication Required
Proxy-Authenticate: Basic realm=”Corporate Proxy”

Reason

The proxy server is requesting HTTP Basic Authentication before forwarding the request.

Solution

Supply valid credentials using the requested authentication method and retry the request.