How to fix web server is down error code 521?

[Author Anshul]

My web browsers are not working, maybe servers are down. And it is showing error code 521. Can I fix it by myself?

 

[Nikhil Rajoria]

Error 521 normally indicates that the origin server is not answering Cloudflare. Review the server firewall, restart the web server, and make it go online.

 

[Jyoti]

Fix Error 521: Web Server Is Down:

1. Make sure your server is online.
2. Whitelist Cloudflare’s IPs in your firewall.
3. Check that your server isn’t blocking Cloudflare.
4. Restart your server.
5. Contact your hosting provider if needed.

This error means Cloudflare can’t reach your site’s server.

 

[mayank]

Error 521 means your web server is not responding to Cloudflare. To fix it, check if your server is online, allow Cloudflare IPs in your firewall, verify SSL settings, and ensure your origin server isn’t blocking requests.