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Windows Defender Authentication Failed: Step-by-Step Checklist - PowerShell 504 Gateway Timeout REST API Fix-PowerShell GET Request 404 Fix

Updated 2026-06-13 19:02:45developer-tools

Windows Defender Authentication Failed: Step-by-Step Checklist - PowerShell 504 Gateway Timeout REST API Fix-PowerShell GET Request 404 Fix

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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