Understanding Cloudflare 520 Error

Origin problem: Cloudflare received an empty or unexpected response from your server.

Common Causes

  • PHP fatal error or timeout
  • Empty response headers
  • Server resource exhaustion

Diagnostic Steps

Bypass Cloudflare

Temporarily pause Cloudflare or edit hosts file to test direct server access.

Check cPanel Error Logs

cPanel → Metrics → Errors → Look for PHP fatal errors at the same time.

Solutions Table

CauseFix
PHP crashIncrease memory_limit and max_execution_time
Large headersReduce cookies or disable unnecessary plugins
Resource limitEnable caching, optimize queries
.htaccess issueRename .htaccess temporarily