Error 520
Error 520 Web Server Returns an Unknown Error Error
What This Error Means
Error 520 is a catch-all response from Cloudflare when the origin server returns something unexpected or something that Cloudflare cannot interpret. It essentially means 'something went wrong, but we are not sure what'.
Common Causes
- The origin server crashed while processing the request.
- Empty or invalid response headers from the origin.
- The origin server connection was reset.
- A firewall on the origin server is blocking Cloudflare IPs.
How to Fix It (For Users)
- 1 Refresh the page.
- 2 Clear your browser cache.
- 3 Try again in a few minutes.
For Site Owners / Developers
- Check your origin server error logs for crashes.
- Disable your .htaccess file temporarily to rule out bad rules.
- Ensure your firewall is not blocking Cloudflare IPs.
- Look for scripts that might be sending empty responses.
When It Is NOT Your Fault
If the issue is a temporary glitch on the origin server.
Check if this outage affects everyone globally
This error often indicates a wider problem. Use our tool to verify if the site is down for everyone.
Check Website Status →Recommended Tool to Prevent This Error
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