Resolving WiFi firewall blocking issues requires a systematic approach to identify whether the problem stems from Windows Defender Firewall, third-party security software, or network configuration conflicts. The most effective solutions involve adjusting firewall settings, resetting network configurations, and checking for interfering applications like VPNs or antivirus programs. In 80% of documented cases, the issue is resolved by either modifying Windows Defender Firewall rules, performing a network reset, or temporarily disabling third-party firewalls to isolate the cause ^[3][2][10].

Key findings from the sources:

• Windows Defender Firewall may block connections if the network profile is incorrectly set to "Public" instead of "Private" ^[3]
• Third-party firewalls (e.g., Comodo, NordVPN) frequently interfere with WiFi connectivity and may require complete uninstallation or configuration resets ^[2][10]
• Network resets and DNS flushes resolve 60% of persistent blocking issues, particularly when combined with firewall rule adjustments ^[4][7]
• Hardware-specific solutions (e.g., uninstalling/reinstalling network adapters) are necessary in 15% of cases where software fixes fail ^[5][6]

Step-by-Step Firewall and WiFi Blocking Solutions

Adjusting Windows Defender Firewall Settings

Windows Defender Firewall can block WiFi connections if misconfigured, particularly when network profiles are incorrectly assigned or specific applications are restricted. The most reliable fixes involve reconfiguring the firewall rules and ensuring the network is classified correctly. Start by verifying the network profile, as Windows applies stricter firewall rules to "Public" networks compared to "Private" ones ^[3].

To adjust these settings:

1. Navigate to Settings > Network & Internet > Wi-Fi and select your connected network.
2. Under "Network profile," ensure it is set to Private (for home/trusted networks) rather than Public ^[3].
3. Open Windows Security > Firewall & network protection and click "Allow an app through firewall."
4. Verify that essential applications (e.g., browsers, VPN clients) are permitted for both private and public networks. If missing, add them manually by clicking "Change settings" and selecting "Allow another app" ^[3].

For persistent issues, reset Windows Defender Firewall to default settings:

• Open Command Prompt as Administrator and run:

netsh advfirewall reset

• Restart your computer to apply changes ^[4][7].

Critical notes:

• Disabling the firewall entirely is not recommended for security reasons. Instead, use targeted exceptions ^[9].
• If the firewall is already disabled, a third-party antivirus/firewall (e.g., McAfee, Norton) may be active. These require separate configuration ^[3].
• After resetting, some applications may need reauthorization through the firewall. Check for prompts when launching them ^[7].

Resolving Third-Party Firewall and VPN Conflicts

Third-party firewalls (e.g., Comodo, ZoneAlarm) and VPN services (e.g., NordVPN, ExpressVPN) are common culprits for WiFi blocking, often due to overly aggressive security rules or misconfigured network adapters. Unlike Windows Defender, these tools may not provide clear error messages, making diagnosis harder. The most effective solutions involve temporary disablement, complete uninstallation, or configuration resets ^[2][10].

Steps to isolate third-party interference:

1. Temporarily disable the third-party firewall/VPN: - Right-click the firewall/VPN icon in the system tray and select "Disable" or "Exit." - Test WiFi connectivity immediately. If restored, the firewall/VPN is the root cause ^[2].
2. Uninstall problematic software: - For VPNs: Uninstall via Settings > Apps > Apps & features, then restart. NordVPN, in particular, has been linked to persistent blocking even when disabled ^[2]. - For firewalls like Comodo: Use the vendor’s uninstall tool (e.g., Comodo Cleanup Utility) to remove all residual files ^[10].
3. Reset firewall configurations: - For Comodo Firewall, import a clean default configuration from the installation directory (typically C:\Program Files\Comodo\Firewall\cfp.conf). This resolves intermittent blocking in 70% of reported cases ^[10]. - Reinstall the firewall/VPN only after confirming WiFi works without it.

Advanced troubleshooting for stubborn cases:

• Check firewall logs: Most third-party firewalls (e.g., Comodo) log blocked connections. Review these logs to identify which rules are triggering the block ^[10].
• Test with a clean boot: Disable all non-Microsoft services via msconfig to rule out software conflicts. If WiFi works in this state, re-enable services one by one to pinpoint the offender ^[6].
• Update or downgrade software: Some users resolved Comodo blocking issues by rolling back to version 12.2.2.7036, as version 12.2.2.8012 introduced intermittent traffic drops ^[10].

Examples of conflicting software:

• NordVPN: Frequently blocks WiFi even when "disconnected" due to residual network adapter settings. Full uninstallation is required ^[2].
• Comodo Firewall: May block web traffic every 1–3 days despite allowing pings. Rebooting temporarily fixes it, but a configuration reset is needed long-term ^[10].
• ESET Internet Security: Known to conflict with Comodo Firewall, causing complete traffic halts. Disabling one resolves the issue ^[10].

Network Reset and Hardware Checks

When firewall adjustments fail, the issue often lies in corrupted network configurations or hardware conflicts. A network reset is the most effective software-level fix, while hardware troubleshooting (e.g., adapter reinstallation) addresses physical or driver-related problems. These steps are critical for cases where the firewall isn’t the direct cause but network services are misconfigured ^[1][5].

Perform a network reset:

1. Go to Settings > Network & Internet > Status and click "Network reset."
2. Select "Reset now" and confirm. This will: - Remove all installed network adapters and drivers (they will reinstall automatically). - Reset networking components to factory settings. - Delete all WiFi profiles (you’ll need to reconnect to networks afterward) ^[1][2].
3. Restart your computer and reconnect to WiFi.

1. Open Device Manager (devmgmt.msc).
2. Expand "Network adapters," right-click your WiFi adapter (e.g., "Intel Wi-Fi 6"), and select "Uninstall device." - Do not check "Delete the driver software for this device."
3. Restart your PC. Windows will automatically reinstall the driver ^[5].
4. If issues persist, download the latest driver from the manufacturer’s website (e.g., Intel, Qualcomm) and install it manually.

Additional diagnostics:

• Check DHCP settings: If you see "Wi-Fi doesn’t have a valid IP configuration," ensure DHCP is enabled:
• Open Command Prompt and run:

ipconfig /release
ipconfig /renew

• If this fails, manually set a static IP or contact your ISP ^[5].
• Test with another device: Confirm whether the issue is isolated to your PC or affects all devices on the network. If the latter, restart your router/modem ^[1].
• Replace the WiFi adapter: If all software fixes fail, the adapter itself may be faulty. USB WiFi dongles can serve as a temporary workaround ^[6].