@Blackwolf HTTP error code 521 typically indicates that the server is down or experiencing connection issues and is unable to process the request. This error specifically refers to the origin web server refusing a connection from Cloudflare, a popular content delivery network service. Here are a few common causes of error code 521: 1. Server downtime: The origin web server may be temporarily unavailable, either due to maintenance, server overload, or other technical issues. 2. Firewall blocking connections: The server may have a firewall or security settings that are blocking incoming connections from Cloudflare's IP addresses. 3. Misconfigured DNS settings: Incorrect DNS configurations can prevent proper communication between the Cloudflare CDN and the origin server. To troubleshoot this issue, you can try the following steps: 1. Check if the server is up and running properly by accessing the website directly without using Cloudflare. 2. Verify that Cloudflare's IP addresses are not being blocked by any firewall or security settings on the server. 3. Review the DNS settings to ensure they are correctly configured to point to the appropriate server. If you continue to encounter error code 521, it may be best to reach out to your web hosting provider or IT support team for further assistance in resolving the issue.