How to Fix Security or Firewall might be blocking the connection [Steps]

What is ‘Security or Firewall might be blocking the connection’ error in Windows 10/11?

If you are facing ‘Security or Firewall might be blocking the connection’ error message when you complete Windows Network Diagnostic in your Windows 10/11 computer, and searching for ways to fix the issue, then you are in right-place for the solution. You will be guided here with easy steps/methods to resolve the issue. Let’s starts the discussion.

‘Security or Firewall might be blocking the connection’ error:

When you run Windows Network Diagnostics in Windows 10/11 computer in order to check why you are facing internet/network connection problem, you may experience ‘Security or Firewall might be blocking the connection’ error as result after network diagnostic process completed. This error message indicates you are unable to access internet/network possibly due to interference of your antivirus/firewall program installed in Windows computer. It might possible your security software/firewall is blocking internet connection in your Windows computer for some reasons that’s why the issue is occurred.

There could be several reasons behind the issue including outdated/corrupted network adapter driver, interference of antivirus/firewall program, incorrect or bad configured Windows Firewall settings, corruption in Windows computer, and other issues. You should make sure network adapter driver is properly installed and is up-to-date to latest & compatible version if you don’t want to face this type of problem. It is possible to resolve the issue with our instructions. Let’s go for the solution.

How to fix Security or Firewall might be blocking the connection error in Windows 10/11?

Method 1: Fix ‘Security or Firewall might be blocking the connection’ issue with ‘PC Repair Tool’

‘PC Repair Tool’ is quick way to find and fix BSOD errors, DLL errors, EXE errors, problems with programs/applications, malware or viruses infections in computer, system files or registry issues, and other system issues with just few clicks.

Method 2: Run Windows Firewall troubleshooter

Windows built-in Windows Firewall troubleshooter can resolve the issue.

Step 1: Download ‘diagcab’ file and official Windows Firewall troubleshooter from Microsoft official site

Step 2: Once downloaded, double-click on the file to run it or open the wizard, and follow on-screen instructions to finish troubleshooting of Windows Firewall troubleshooter. Once finished, check if the issue is resolved.

Method 3: Restore/reset Windows Firewall setting to default

Incorrect or bad configured firewall settings could be a reason behind the issue. You can fix the issue by performing Windows Firewall settings reset/restore to default.

Step 1: Open ‘Control Panel’ app in Windows PC via Windows Search Box and go to ‘System and Security > Windows Defender Firewall’

Step 2: On the opened page, click ‘Restore Defaults’ link on left-pane, and click ‘Restore Defaults’ button and confirm resetting. One done, close Control Panel app and check if the issue is resolved.

Method 4: Disable your third-party antivirus/firewall

This issue can be occurred due to interference of third-party antivirus/firewall program installed in computer. You can fix the issue by disabling your third-party antivirus/firewall program, and then check if the issue is resolved.

Method 5: Run Network troubleshooter

You can run Windows built-in network troubleshooter to fix the issue.

Step 1: Open ‘Settings’ app in Windows PC via Windows Search Box and go to ‘System > Troubleshoot > Other Troubleshooters’

Step 2: Find and select ‘Network troubleshooter’, and click ‘Run’ to run the troubleshooter, and follow on-screen instructions to finish troubleshooting. Once done, check if the issue is resolved.

Method 6: Update Killer network adapter driver

Killer Network Manager or Killer Control Center is a tool from Intel.com designed to help prioritize the network bandwidth to applications or process that require faster internet connections. Howeer, if you are facing the problem relating to network connection , then updating Killer network adapter driver to latest & compatible version can resolve the issue.

Step 1: Open ‘Device Manager’ app in Windows PC via Windows Search Box and expand ‘Network Adapters’ category

Step 2: Find and right-click on your network adapter, and select ‘Update Driver’ and follow on-screen instructions to finish updating. Once updated, restart your computer and check if the issue is resolved.

Download or reinstall network adapter driver update in Windows PC [Automatically]

You can also try to update all Windows drivers including network adapter driver using Automatic Driver Update Tool. You can get this tool through button/link below.

Method 7: Perform System Restore

If the issue is still persist, you can try to fix the issue by performing system restore in computer.

Step 1: Press ‘Windows + R’ keys on keyboard, type ‘rstrui’ in ‘Run’ window and hit ‘Ok’ button to open ‘System Restore’ app

Step 2: Click ‘Next’, select a valid restore point according to date & time when there was no issue at all in computer, and click ‘Next > Finish’ to start restoring process. Once done, check if the issue is resolved.

Conclusion

I am sure this post helped you on How to fix Security or Firewall might be blocking the connection error in Windows 10/11 with easy ways. You can read & follow our instructions to do so. That’s all. For any suggestions or queries, please write on comment box below.