typically occurs when the firewall detects a loss of reliability in reaching the categorization servers or if there is an authorization failure with the third-party service ( Common Causes DNS Reliability Check Failure
The filter relies on *.zvelo.com for categorization. If your DNS is failing to resolve this, the filter will deactivate. Go to in the admin interface. Enable Custom DNS forwarding . typically occurs when the firewall detects a loss
If you are still experiencing issues with your web filter, please let me know: What of Kerio Control you are running. If you recently renewed or changed your license . Enable Custom DNS forwarding
💡 If the filter deactivates frequently, check your internet link speed. Slow links can trigger the "unreliable" flag, which the SSH fix above permanently ignores. Using Kerio Control Web Filter 💡 If the filter deactivates frequently, check your
If the firewall cannot reach the cloud servers, categorization will fail. Go to > DNS .
After applying the fixes, you must ensure the filter itself is enabled in the settings.