Optimizing Windows File Protection Service

To optimize the Windows File Protection service (WFP), you can increase the %SystemRoot%\System32\Dllcache folder to its maximum size to eliminate the need to have media inserted to replace files.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

NOTE: You should use Ntbackup.exe in Windows 2000 to back up the system state before following the steps in this article.

Maximizing the Dllcache Folder

1. Use Registry Editor (Regedt32.exe) to locate the following value:
   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SFCQuota
2. Set the SFCQuota value to 0xFFFFFFFF. This value caches all protected files.
3. Quit Regedt32.exe.
4. Type sfc /scannow at a command prompt. This causes the System File Checker tool to verify all protected file versions and add all absent protected files to the Dllcache folder.

Both the SFCQuota and SFCDllCacheDir values can be set during unattended Setup. For additional information about WFP, please see the following articles in the Microsoft Knowledge Base: Windows 2000 fills the Dllcache up to its cache size limit until you reach 150 MB of free space remaining. If you have 150 MB or less of free space remaining with the installation of Windows 2000, your Dllcache should be empty. By default, Windows 2000 (all versions) is set to cache all protected files.

NOTE: Windows 2000 may not have all files cached until you have run a system scan using SFC /Scannow.