diff --git a/windows/security/threat-protection/windows-defender-antivirus/microsoft-defender-atp-mac-whatsnew.md b/windows/security/threat-protection/windows-defender-antivirus/microsoft-defender-atp-mac-whatsnew.md
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+++ b/windows/security/threat-protection/windows-defender-antivirus/microsoft-defender-atp-mac-whatsnew.md
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+## 100.65.28
+
+- Added support for macOS Catalina