The consequences of having an inactive web filter and disabled categorization include:
Kerio Control uses DNS queries to reach its update and categorization servers. If your ISP or current DNS configuration is slow or blocking these requests, the filter will deactivate.
To avoid this issue in the future, consider the following best practices: The consequences of having an inactive web filter
Before fixing the problem, you must understand the architecture. Kerio Control uses a cloud-based (formerly McAfee, now partially proprietary and third-party) to categorize websites (e.g., “Social Networking,” “Streaming Media,” “Phishing”).
Kerio Control 依赖 DNS 查询来获取 Zvelo 服务的授权令牌 (token)，此令牌有效期为 21 天。使用某些公共 DNS 服务器（如 Google 的 8.8.8.8）有时会导致这种令牌交换出现问题。 Kerio Control uses a cloud-based (formerly McAfee, now
: Ensure your firewall can resolve external domains. It is recommended to use Cloudflare (1.1.1.1) or OpenDNS (208.67.222.222) as custom DNS servers for *.zvelo.com URLs to avoid authorization failures.
If a new version is available, back up your current configuration and upgrade immediately. If a new version is available, back up
If the service is stuck in a frantic "hot" retry loop, force a reset:
This comprehensive troubleshooting guide explains why this critical error occurs and provides step-by-step instructions to restore your network security. Why the Kerio Control Web Filter Deactivates