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How to Fix Cloudflare 521 Error During Setup - Windows Defender Real-Time Protection Not Working? Fix It Here-Stop Antivirus from Causing Chrome Connection Reset Errors

Updated 2026-07-28 16:09:28developer-tools

How to Fix Cloudflare 521 Error During Setup - Windows Defender Real-Time Protection Not Working? Fix It Here-Stop Antivirus from Causing Chrome Connection Reset Errors

Prepare

Execute

Validate

Document

Operational follow-up

Record the exact option, command, or setting that changed the result.
Keep a rollback note if the workflow affects shared files or team settings.

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