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OpenVPN Connection Failed: Check Firewall Settings - Troubleshooting Cloudflare 521: Server Not Reachable-Troubleshoot Windows Defender Lag and High CPU

Updated 2026-06-14 02:38:01office-tools
OpenVPN Connection Failed: Check Firewall Settings - Troubleshooting Cloudflare 521: Server Not Reachable-Troubleshoot Windows Defender Lag and High CPU
Likely symptom
Likely cause
Safe rollback

Verification route

  • Repeat the original action, not only a simplified test case.
  • Restart the app or reload the service after configuration changes.