Troubleshooting the “Proxy server is refusing connections” Issue on Firefox

The most common use of proxies is within a company. Companies often use a proxy server to “filter” all Internet traffic.

This proxy server is part of a two-way form of communication.

  • Incoming Internet traffic is checked for malicious attacks.
  • Outgoing Internet traffic is filtered for employees trying to access inappropriate Web sites.

In some cases, the private Internet Service Provider (ISP) you use at home may also require you to use a proxy server. However, your browser usually has full access to the Internet even without a proxy server.

The error occurs when you change the proxy configuration either on your computer or in your browser. It may be caused by malicious software. It is also possible that someone accidentally changed the proxy settings in Firefox.

What causes the error message “Proxy server is refusing connections” in Firefox?

This problem mostly occurs when you have an incorrect or faulty proxy server configuration or when using the VPN service. However, this problem can also occur if your computer is attacked by malware that may have changed some internal settings.

How to resolve the “Proxy server refuses to connect” error in Firefox?

Turn off the built-in proxy server

  1. Press the Windows + R keys to open the Run dialog box.
  2. Type ms-settings:network-proxy and press Enter to open the Proxy tab in the Settings menu.
  3. Scroll down the right-hand menu to the Manual Proxy Settings section.
  4. Disable the Use a proxy server option.
  5. Restart your computer.

Make Firefox use automatic proxy detection

  1. Open the Mozilla Firefox browser.
  2. Click the action button in the upper right corner of the screen.
  3. From the pop-up menu, select Settings or Preferences.
  4. Select the General category from the left-hand vertical menu.
  5. Scroll down the right-hand menu to Network Settings.
  6. Tap the Settings button to open the Advanced menu.
  7. Set Internet Access Setup to Automatically detect proxy settings for this network.
  8. Click Ok to save your changes, then restart your Firefox browser.

Add a URL’s SSL port to the list of allowed connections

  1. Scan the URL causing the error to see which port is active for HTTPS.
  2. Open the proxy configuration settings and find the option to add the port as an alternative SSL port.
  3. Save the configuration changes and reboot the computer.

Remove the VPN client

  1. Press the Windows + R keys to open the runtime window.
  2. Type appwiz.cpl and press Enter to open the Programs and Features window.
  3. If prompted by User Account Control (UAC), click Yes to grant administrator rights.
  4. Scroll through the list of installed applications and find the VPN client you are using, right-click it and select Uninstall from the context menu.
  5. Follow the instructions on the screen to complete the uninstallation, then restart your computer.

Frequently Asked Questions

  1. Reset Internet settings.
  2. Disable proxy server.
  3. Use VPN.
  4. Check your computer for malicious programs.
  5. Use ipconfig command.
  6. Reset Chrome to default settings.
  7. Uninstall all suspicious applications.
  8. Edit your registry.

If you get the message "Cannot connect to the proxy server," the problem may be caused by a malware infection. Some malware can disrupt your Internet connection or change proxy settings without your knowledge.

Click the Network tab, then click Settings. In the connection settings window, select No proxy. (The Use system proxy settings option is also acceptable). This will use the standard Windows proxy settings.

  1. Check proxy settings in your browser.
  2. Disable proxy server on your local network.
  3. Disable manual proxy configuration in your settings.
  4. Check your VPN.
  5. Check your computer for malware.
  6. Clear your browser cache.