diff --git a/windows/security/threat-protection/TOC.md b/windows/security/threat-protection/TOC.md
index d96b9d9dc8..cf34540df2 100644
--- a/windows/security/threat-protection/TOC.md
+++ b/windows/security/threat-protection/TOC.md
@@ -15,6 +15,7 @@
 ##### [Data storage and privacy](windows-defender-atp\data-storage-privacy-windows-defender-advanced-threat-protection.md)
 ##### [Assign user access to the portal](windows-defender-atp\assign-portal-access-windows-defender-advanced-threat-protection.md)
 #### [Onboard machines](windows-defender-atp\onboard-configure-windows-defender-advanced-threat-protection.md)
+##### [Onboard previous versions of Windows](onboard-downlevel-windows-defender-advanced-threat-protection.md)
 ##### [Onboard Windows 10 machines](windows-defender-atp\configure-endpoints-windows-defender-advanced-threat-protection.md)
 ###### [Onboard machines using Group Policy](windows-defender-atp\configure-endpoints-gp-windows-defender-advanced-threat-protection.md)
 ###### [Onboard machines using System Center Configuration Manager](windows-defender-atp\configure-endpoints-sccm-windows-defender-advanced-threat-protection.md)