Disable: 'Turn on reparse point scanning' This policy setting allows you to configure reparse point scanning. If you allow reparse points to be scanned, there is a possible risk of recursion. However, the engine supports following reparse points to a maximum depth so at worst scanning could be slowed. Reparse point scanning is disabled by default and this is the recommended state for this functionality. If you enable this setting, reparse point scanning will be enabled. If you disable or do not configure this setting, reparse point scanning will be disabled. Counter Measure: Configure this setting depending on your organization's requirements. Potential Impact: Reparse point scanning can impact performance.

(1) GPO: Computer Configuration\Administrative Templates\Windows Components\Windows Defender\Scan\Turn on reparse point scanning (2) REG: HKEY_LOCAL_MACHINE\Software\Policies\Microsoft\Windows Defender\Scan\DisableReparsePointScanning