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MC1227621 — Microsoft Defender Antivirus: Change to exclusion storage when using MDE security settings management

MC1227621Microsoft Defender XDRplanForChangeUpdated: 13 February 2026

Starting March 2026, Microsoft Defender Antivirus with MDE security settings will stop storing readable exclusions in the local registry. Organizations must use PowerShell cmdlets like Get-MpPreference to retrieve settings. Registry-based monitoring will no longer work; update scripts and notify teams accordingly.

Applies to: Microsoft Defender XDR
Source: mc.merill.net — data via Merill Fernando's open archive (MIT).