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Home / developer-tools / Fix OneDrive Sync Error 0x8004de40 – Authentication Failure - Windows Defender 502 Bad Gateway: How to Fix-Windows Defender Turned Off by Group Policy: Troubleshooting Guide

Fix OneDrive Sync Error 0x8004de40 – Authentication Failure - Windows Defender 502 Bad Gateway: How to Fix-Windows Defender Turned Off by Group Policy: Troubleshooting Guide

Updated 2026-06-14 01:08:22developer-tools
Fix OneDrive Sync Error 0x8004de40 – Authentication Failure - Windows Defender 502 Bad Gateway: How to Fix-Windows Defender Turned Off by Group Policy: Troubleshooting Guide
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