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How to Fix Cloudflare 521 Error During Setup - How to Resolve Docker Exit Code 137 Immediately-How to Fix BITS Service Causing Update Hang on Windows 11

Updated 2026-07-28 11:59:26browser-issues

How to Fix Cloudflare 521 Error During Setup - How to Resolve Docker Exit Code 137 Immediately-How to Fix BITS Service Causing Update Hang on Windows 11

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.