This policy setting allows you to set when Windows File Protection scans protected files. This policy setting directs Windows File Protection to enumerate and scan all system files for changes.If you enable this policy setting select a rate from the "Scanning Frequency" box. You can use this setting to direct Windows File Protection to scan files more often.-- "Do not scan during startup" the default scans files only during setup.-- "Scan during startup" also scans files each time you start Windows XP. This setting delays each startup.If you disable or do not configure this policy setting by default files are scanned only during setup.Note: This policy setting affects file scanning only. It does not affect the standard background file change detection that Windows File Protection provides.
System\Windows File Protection
Machine
Windows Server 2003 Windows XP and Windows 2000 only
HKLM\Software\Policies\Microsoft\Windows NT\Windows File Protection!SfcScan
WindowsFileProtection.admx