12 Best Fixes For PR_CONNECT_RESET_ERROR on Mozilla Firefox

pr_connect_reset_error

When your browser can’t connect to the server it’s trying to connect to, you’ll get PR_CONNECT_RESET_ERROR on Firefox with the message ‘Secure Connection Failed.’

Additionally, it’ll say that you can’t access the page because ‘the authenticity of the received data could not be verified.’ If you’re frequently seeing this error on Firefox, learn what it is, what its causes are, and how to fix it.

What Is PR_CONNECT_RESET_ERROR on Firefox?

When you enter a website on your web browser, many different connections begin between your browser and the website (the server). If your browser detects that the server isn’t secure, it may block the server connection, and you’ll get PR_CONNECT_RESET_ERROR or PR_END_OF_FILE_ERROR.

When this identical situation happens on Chromium-based browsers (Google Chrome, Microsoft Edge, and Opera), you’ll see the ERR_CONNECTION_RESET error message.

What Are the Causes of PR_CONNECT_RESET_ERROR on Mozilla Firefox?

  • TCP Protocol filtering
  • Browsing data saved on the browser is corrupted
  • A firewall or antivirus is blocking the browser or the website
  • VPN or proxy settings are interrupting the connection
  • The website’s security settings don’t allow connections from proxies
  • Your ISP has blocked the website
  • An add-on is interrupting the connection
  • The web browser is buggy

Best Methods to Solve PR_CONNECT_RESET_ERROR on Firefox for Windows, Linux, and Mac

Make sure to restart your computer as some problems are fixed by rebooting your PC. After this, use these methods to fix PR_CONNECT_RESET_ERROR on Firefox. These fixes are focused on Windows 7, 8, 10, and 11, but many fixes also apply to Mac and Linux computers.

  1. Check Your Internet
  2. Clear Cache and Browsing Data
  3. Temporarily Turn off Your Firewall or Allow Firefox Through Firewall
  4. Disable or Remove Firefox Add-ons (Extensions)
  5. Disable Your VPN or Proxy Connection
  6. Bypass Geo-Lock by Using a VPN
  7. Turn Off TCP Protocol Filtering of Your Security Software
  8. Temporarily Disable Your Antivirus or Security Application
  9. Enable DNS over HTTPS on Firefox
  10. Make Sure Your Internet isn’t Restricted (School, University Internet)
  11. Uninstall and Reinstall Firefox
  12. Open the Website on Another Web Browser

1. Check Your Internet

You should open other websites on your browser to check if the issue is with the website or if the internet connection itself is problematic. 

If no website is opening, check your internet connection:

  • Restart your router
  • Disconnect unnecessary devices from the Wi-Fi
  • Test your internet speed
  • Use a VPN or disable VPN if you’re using one (Method 5 and 6)

If only one or a few websites are showing this error while others are opening fine, try every method in this guide. 

2. Clear Cache and Browsing Data

Your browser cache, cookies, and browsing data are saved to keep a record of your browsing, preferences, website logins, and temporary data to load websites quickly.

If this data is corrupted or conflicts with a website or its settings, you may encounter problems like PR_CONNECT_RESET_ERROR. So, clear your browser cache and check if it fixes the issues.

If not, clear the whole browsing data. Make sure that all Firefox tabs are closed except the new tab you open to clear data.

2.1 Clear Cache on Firefox

  • Click the three horizontal lines at the top right corner of the browser.
  • Choose ‘Settings’ from the menu.
Hamburger options menu on Firefox
  • From the side pane, go to ‘Privacy & Security.’
  • Scroll down. Under the ‘History’ section, click the ‘Clear History’ button.
Privacy & Security settings on Firefox web browser
  • Choose ‘ Everything’ from the drop-down menu at the top of the new window next to ‘Time range to clear.’
  • Uncheck everything and checkmark ‘Browsing & download history’ and ‘Cache.’
Clear All History on Mozilla Firefox
  • Click OK.

OR

  • Open Firefox.
  • Press CTRL + SHIFT + DEL on your keyboard.
  • Select ‘Browsing & download history’ and ‘Cache.’
  • Click OK.

2.2 Clear Entire Browsing History on Firefox

If clearing the cache doesn’t fix the issue, clear your entire browsing data on Firefox. This will delete your saved logins, browsing history, and site preferences.

  • Open Firefox and go to Settings > Privacy & Security > Clear History.
  • Select ‘Everything’ from the drop-down menu next to ‘Time range to clear.’
  • Checkmark all the boxes.
  • Click OK.

3. Temporarily Turn off Your Firewall or Allow Firefox Through Firewall

A firewall acts as a bodyguard between your computer and the internet. It only allows authorized connections and discards all others. But if your Firewall is overprotective, it might detect a regular website or browser as a threat and block its access to the internet.

In turn, you’ll find that your browser isn’t connecting to the internet or a specific website is not opening, and the browser is showing the message PR_CONNECT_RESET_ERROR.

You have two options to check this:

3.1 Allow Firefox Through Firewall

If your browser isn’t opening any website, enable it on your Firewall application. Here’s the method for Windows Defender Firewall:

  • Open the Start menu, type ‘Windows Firewall,’ and open the first app you see.
  • Select ‘Allow an app through firewall’.
Firewall & network protection window on Windows 10
  • On the new window, find Mozilla Firefox or Firefox in the list and make sure that it’s check-marked, which means it’s allowed.
  • Click ‘Change settings,’ checkmark Firefox, and click OK if it isn’t.
Allow Firefox through Firewall on Windows 10/11

3.2 Temporarily Disable Firewall

In case Firefox can open other websites, and one or few websites aren’t opening, disable your firewall temporarily.

  • Open Windows Defender Firewall by clicking the Start menu, typing ‘Windows Firewall,’ and selecting the app.
  • Choose your network. You’ll see (Active) written next to it.
Firewall & network protection window on Windows 10
  • Switch the toggle to off under ‘Windows Defender Firewall’.
Public network settings on Windows Security. Enable or Disable Windows Firewall
  • Restart your computer and try opening the website again.

If you have a third-party Firewall, open the application and look for an option to turn it off.

Furthermore, make sure to turn on your firewall after troubleshooting the problem.

4. Disable or Remove Firefox Add-ons (Extensions)

Some add-ons (extensions) interrupt your browser’s connection with websites. It could be a security add-on detecting a false positive threat, an ad blocker add-on blocking the website, a proxy add-on that’s incorrectly configured or not responding, or any other add-on.

When they disabled a coupon code searching add-on on Firefox, some users reported that their PR_CONNECT_RESET_ERROR problem was fixed.

  • Open Firefox browser.
  • Click the three horizontal lines (hamburger icon) at the top right corner and choose ‘Add-ons and themes.’
  • Disable all the extensions by clicking the toggle next to each extension.
Extensions settings on Firefox
  • Restart your browser and try opening the website again.

5. Disable Your VPN or Proxy Connection

VPN clients and proxy connections directly connect with your internet connection to mask or hide your real IP address. If the VPN isn’t configured correctly, or it’s not responding, or the website you’re visiting has blacklisted proxies, or the VPN is conflicting with your browser (or internet) settings, you may see the pr connect reset error on Firefox. So, disable your VPN or proxy and try again.

  • Open your active VPN client.
  • Click the Disable button or any other similar switch.

For manual proxies set up on Windows, follow these steps to disable them:

  • Click the internet/Wi-Fi icon on the taskbar and select ‘Network & Internet settings.
  • From the side panel, go to ‘Proxy.’
  • Under the Manual proxy setup section, turn off ‘Use a proxy server’.
Proxy settings on Windows 10
  • Restart your computer.

If you disabled the VPN client and the connection issue persists on Firefox, uninstall it completely.

  • Open the Start menu, type ‘add or remove’, and select the first app.
  • Find the VPN application and click it to see the uninstall option.
  • Select ‘Uninstall’.
  • Restart your computer.

6. Bypass Geo-Lock by Using a VPN

We discussed in the last section that VPNs and proxies could conflict with your internet settings. But in this section, we’re encouraging you to use a VPN. Why so? The VPN disabling fix was for users who were already using a VPN or proxy. But if you don’t have any VPN installed or proxy enabled, you should try using a VPN

This is because of the possibility that your ISP blocks the website you’re trying to visit. To unblock websites that aren’t accessible in your region, you should employ a VPN app.

  • Open a web browser (if you can open other websites) and search on Google ‘free VPNs’.
  • Read the lists of best free VPNs and then try some of them to find a good VPN.

7. Turn Off TCP Protocol Filtering of Your Security Software

TCP Protocol Filtering is an internet security feature included in most antivirus applications that offer web protection as well. It ensures that your computer connects to secure connections and discards suspicious connections.

But, in some instances, it may detect secure connections as suspicious and block them. When this happens, you see the PR_CONNECT_RESET_ERROR.

Any antivirus suite can be responsible for this, but ESET antivirus software has been reported to have an overprotective TCP protocol filtering system. 

The method for disabling TCP protocol filtering on every security application differs. We’ll show the steps for turning it off on ESET.

  • Open ESET antivirus.
  • Navigate to the Advanced setup.
  • Select ‘Web and Email’ from the left panel.
  • Toggle off ‘Protocol Filtering.’
  • Click OK.

8. Temporarily Disable Your Antivirus or Security Application

If you still encounter PR_CONNECT_RESET_ERROR on Firefox after disabling Protocol Filtering, any other feature of the antivirus may be causing the issue. To know if your antivirus is overprotective and blocking your access to a website or a few websites, turn it off temporarily.

Below steps are for Windows Defender Antivirus:

  • Click Start, type ‘Windows Security,’ and choose the app.
  • Select ‘Virus & threat protection.
  • Now, choose ‘Manage Settings’ that’s under the section ‘Virus & threat protection settings.’
  • Turn off ‘Real-time protection.
  • Restart your computer.
  • Open the website on Firefox.

Make sure to turn on your antivirus if it wasn’t the cause of the error.

9. Enable DNS over HTTPS on Firefox

If we consider that the issue of PR_CONNECT_RESET_ERROR is really a browser issue, you can make the browser request that DNS queries are encrypted and sent via HTTPS. This is called DNS over HTTPS or DoH for short. It’s not a completely secure method of connection, but it’s been helpful in fixing the ‘Secure Connection Failed’ issue on Firefox.

  • Open Firefox.
  • Click the three horizontal lines at the top right corner of Firefox and choose ‘Settings.’
  • Scroll down to the end of the ‘General’ settings section.
  • Under ‘Network Settings’, click the ‘Settings’ button.
General Settings on Firefox. Network Settings.
  • On the next screen, scroll down and checkmark ‘Enable DNS over HTTPS’.
Connection Settings on Firefox
  • Click OK.
  • Restart Firefox.

10. Make Sure Your Internet isn’t Restricted (School, University Internet)

The internet in schools, universities, and business offices has restrictions. They don’t allow everything online and depending on their rules. Many websites are blocked so students or employees focus on studies or work.

If you’re seeing PR_CONNECT_RESET_ERROR and you’re accessing the internet from school or work, your IT administrator may have blocked the website. It’s more probable when you can visit other websites, but some websites give that error. To fix this, you can do two things:

  • Ask the administrator to unblock the website.
  • Use your phone’s data connection or any other internet connection.

You should try using a different internet connection even if you’re not on a school or work network.

11. Uninstall and Reinstall Firefox

In some cases, Firefox and other browsers become buggy when used for a long time, even when they’re updated. This is due to corrupted files, incorrect settings, outdated browser versions, or other reasons. To be sure that the browser itself isn’t glitching, you should uninstall Firefox and then reinstall it. Follow these steps on Windows:

  • Click Start, type ‘add or remove,’ and select the app ‘Add or remove programs.’
  • Find Mozilla Firefox in the list of installed programs.
  • Click Mozilla Firefox and select ‘Uninstall.’
Apps & features on Windows 10. Uninstalling Firefox.
  • Follow the on-screen instructions to uninstall Firefox.
  • Restart your computer.
  • Open Microsoft Edge on your computer (it’s pre-installed on every Windows computer).
  • Visit the Mozilla Firefox page, and select the correct version to download it.
  • Open the installation file and install Firefox.
  • Visit the website that was showing PR_CONNECT_RESET_ERROR. 

12. Open the Website on Another Web Browser

If you reached this section, it means the above fixes didn’t work for you. So, try using another web browser because it’s possible that this error is showing up on Firefox only.

  • Open the website on Microsoft Edge that’s already installed on your computer.
  • If Edge doesn’t open it, install Google Chrome and open the website on it.
  • If it fails, install Opera and try again.

We also recommend combining this solution with Methods 5 and 6. Use a different browser and disable your VPN connection or install a VPN if you’re not using any.

Conclusion

There can be many different reasons for the PR_CONNECT_RESET_ERROR message on Firefox. Try all the 12 solutions above to fix it.