How to Resolve ‘Proxy server is refusing connections’ Error on Firefox

Some Mozilla Firefox users are encountering the ‘The Proxy server is refusing connections‘ error when they’re attempting to access certain websites. In most cases, affected users are reporting that the same problem doesn’t occur when they try to access the same website from a different browser.

‘The Proxy Server is refusing connections’ on Mozilla Firefox

In Firefox, this particular issue means that while your system is able to talk to the proxy, but the service is not letting the browser to forward the data that it needs in order to display the web page that you’re trying to visit.

In most cases, this happens due to the fact that your Proxy solution requires some type of authentication, but Firefox isn’t configured to use the system’s proxy. If this scenario is applicable, you can get the issue resolved by forcing your Firefox browser to Auto Detect the Proxy settings used by your system (Method 1).

Another potential scenario that will cause this problem is if the proxy server does NOT allow SSL on the port you are trying to connect to. This can be fixed by accessing your Proxy configuration and adding that SSL port to the list of allowed items (Method 2).

In case you encounter this error while attempting to access an FTP site through an HTTP proxy, the error will no longer appear once you move to a more secure HTTPS proxy (Method 3).

And if all else fails, you should start considering disabling the Proxy server that you’re using (Method 4) or uninstalling the VPN client (Method 5).

Method 1: Forcing Firefox to Auto Detect Proxy Settings

As it turns out, this particular issue can also occur due to the way Firefox is configured to treat proxy servers by default. Unlike many of the other proxy servers, Firefox will not adopt the system-wide proxy services that are being used for the network that you’re currently connected to.

Fortunately, you can modify the default settings in order to force the browser to Auto-detect proxy settings for this network, which will end up resolving the issue. Several affected users have confirmed that this operation finally allowed affected users to visit every website without encountering the ‘The Proxy server is refusing connections‘ error.

Here’s a quick guide on accessing the Network Settings of Mozilla Firefox and modifying the default Connection Settings so that the network-wide proxy HTTP and port is adopted:

  1. Open up your Mozilla Firefox browser and click on the action button in the top-right section of the screen. From the newly appeared context menu, click on Options.
  2. Once you’re inside the Options tab, select the General category from the vertical menu on the left, then use the right-hand side menu to scroll all the way down to Network Settings. When you get there, click on Settings to bring up the advanced menu.
  3. After you manage to reveal the Connection Settings menu, simply change the toggle associated with Configure Access to the internet to ‘Use system proxy settings‘.
  4. As soon as you make this modification, click Ok to save the changes, then restart your browser and attempt to access the same web-page that was previously failing.
Forcing Firefox to use the system’s proxy server

In case the same ‘The Proxy server is refusing connections‘ error is still occurring, move down to the next potential fix below.

Method 2: Adding URL SSL port to the allowed list (if applicable)

Another scenario that will cause this issue is a situation in which the end-user tries to access a URL that contains an alternate port for an SSL connection. Some Proxy solutions including EdgeWave iPrism will treat this as a possible security violation.

If this scenario is applicable, you can get the issue resolved by going to your proxy server configuration and adding the port an alternate SSL port.

Of course, the steps of doing this will be way different depending on which Proxy solution you’re using. But in order to make things easier for you, here is a general guideline that you can use in order to add the blocked SSL port to the allowed list:

  1. Analyze the URL that is triggering the ‘The Proxy server is refusing connections‘ error to see if it contains any evidence of a port that is being actively used.
    Checking the URL for evidence of an SSL port
  2. After you manage to identify the problematic port, open your proxy configuration settings and look for a setting that will allow you to add the port as an alternate SSL port.
    Adding the HTTPS port as an alternate SSL port in your Proxy configuration
  3. Once you do this, save the configuration and restart your computer.
  4. After the next startup is complete, see if the problem is resolved at the next computer startup.

In case this issue is still not resolved after following the instructions below or this method was not applicable, move down to the next potential fix.

Method 3: Switching to an HTTPS Proxy (if applicable)

You might also be encountering the ‘The Proxy server is refusing connections‘ error while trying to access an FTP site through an HTTP proxy. As opposed to HTTPS proxies, HTTP proxy servers don’t allow that.

If this scenario is applicable, you can get the issue resolved by making the switch to an HTTPS proxy solution that ensures communications with end-to-end security. In case you don’t want to pay for a premium service, you can use this site to find viable SSL Proxy servers that you can use.

In the event that you aren’t encountering the issue when trying to access a site with FTP functionality, move down to the next potential fix below.

Method 4: Disabling the built-in proxy server (if applicable)

Another scenario that will end up spawning this issue is if a proxy server is enabled in your Local Area Network (LAN) settings without you knowing about. Even if you’re willingly using a dedicated Proxy solution, you should take a trick to the Internet Properties tab and see if you’re not actually using two proxies at the same time.

This regularly occurs after a computer has been attacked by malware or adware – Some viruses will deliberately adjust your proxy settings in order to redirect you towards spammy advertisements.

A lot of affected users have reported that they managed to fix the issue entirely after they disabled the built-in proxy function from the Internet Properties tab.

How to disable built-in proxy on Windows 10

  1. Open up a Run dialog box and press Windows key + R. Next, type ‘ms-settings:network-proxy’ and press Enter to open up the Proxy tab of the Settings menu.
    Run dialog: ms-settings:network-proxy
    Run dialog: ms-settings:network-proxy
  2. Once you’re inside the Proxy tab, use the right-hand side menu to scroll down to the Manual Proxy setup section and disable the toggle associated with Use a proxy server.
    Disabling the use of a proxy server
  3. Once this modification is enforced, restart your computer and see if the issue is resolved at the next computer startup.

How to disable built-in proxy on Windows 7, Windows 8.1

  1. Press Windows key + R to open up a Run dialog box. Inside the text box, type ‘inetcpl.cpl’ inside the text box and press Enter to open up the Internet Properties tab.
    Opening the Internet Properties screen
  2. After you manage to open the Internet Properties tab, select the Connections tab from the horizontal menu at the top, then click on LAN Settings (under Local Area Network LAN settings).
    Open LAN settings in Internet Options
  3. Once you manage to get inside the Local Area Network (LAN) Settings menu, go to the Proxy server setting and uncheck the box associated with ‘Use a proxy server for your LAN’

    Disabling the Proxy server
  4. Once the Proxy server has been disabled, restart your computer and see if the issue is resolved at the next computer startup.

In case the ‘The Proxy server is refusing connections’ error persists, move down to the next potential fix below.

Method 5: Uninstalling VPN Client (if applicable)

As it turns out, Firefox does not have a specific error message pointing towards a problem caused by a VPN network. So in case you’re using a VPN client that actually facilitates the apparition of this issue, you can expect to still get the same error message (The Proxy server is refusing connections).

If this scenario is applicable, you can get the issue resolved simply by disabling the VPN client that is causing the issue. If that’s not an option, the only remaining option is to uninstall the VPN solution altogether.

In case you’ve run out of options, here’s a quick guide on uninstalling the VPN client from your computer:

  1. Press Windows key + R to open un a Run dialog box. Inside the text box, type ‘appwiz.cpl’ and press Enter to open up the Programs and Features screen. When you’re prompted by the UAC (User Account Control), click Yes to grant administrative privileges.
    Typing in “appwiz.cpl” in the Run prompt
  2. Inside the Programs and Features screen, scroll down through the list of installed applications and locate the VPN client that you’re actively using. After you manage to find the VPN solution, right-click on it and choose Uninstall from the newly appeared context menu.
    Uninstalling a VPN tool
    Uninstalling the VPN tool
  3. Follow the on-screen prompts to complete the uninstallation, then restart your computer and see if the issue is resolved at the next system startup.
ABOUT THE AUTHOR

Kevin Arrows


Kevin Arrows is a highly experienced and knowledgeable technology specialist with over a decade of industry experience. He holds a Microsoft Certified Technology Specialist (MCTS) certification and has a deep passion for staying up-to-date on the latest tech developments. Kevin has written extensively on a wide range of tech-related topics, showcasing his expertise and knowledge in areas such as software development, cybersecurity, and cloud computing. His contributions to the tech field have been widely recognized and respected by his peers, and he is highly regarded for his ability to explain complex technical concepts in a clear and concise manner.