How to fix error error-ipsec-ike-critical-payload-not-recognized in Windows 11

Solution Steps

1. 1 Press Windows key + I to open Settings. Go to Network & Internet → VPN. If you have a VPN configured, note the connection name and settings. This step helps you understand your current configuration before making changes.
2. 2 Press Windows key + X and select 'Device Manager'. Expand 'Network adapters'. Right-click your network adapter (e.g., Intel, Realtek) and select 'Update driver'. Choose 'Search automatically for drivers'. This ensures your network driver is up-to-date, as outdated drivers can cause IPsec issues.
3. 3 Open Command Prompt as Administrator (Windows key + X → Terminal (Admin)). Run the command 'netsh advfirewall reset'. This resets the Windows Firewall settings to default, which can clear any corrupted IPsec rules. Note that this will reset all firewall rules, so you may need to re-add any custom rules.
4. 4 If you use third-party VPN software, temporarily uninstall it and try connecting using Windows built-in VPN (Settings → Network & Internet → VPN → Add VPN). This helps determine if the third-party software is causing the issue.
5. 5 Run 'sfc /scannow' in Command Prompt to check for system file corruption. This command scans and repairs protected system files, which can resolve underlying issues that affect IPsec.