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Fix Cloudflare 521 Error Due to Server Overload - npm Run Build Failed: Common Fixes-How to Turn On Defender Real-Time Protection Using Group Policy

Updated 2026-07-28 07:02:11developer-tools

Fix Cloudflare 521 Error Due to Server Overload - npm Run Build Failed: Common Fixes-How to Turn On Defender Real-Time Protection Using Group Policy

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.