Increase in Hard Disk Space Usage After Windows 2000 Upgrade (244861)


The information in this article applies to:

  • Microsoft Windows 2000 Server
  • Microsoft Windows 2000 Advanced Server
  • Microsoft Windows 2000 Professional
This article was previously published under Q244861
IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you upgrade to Windows 2000, your computer may use more hard disk space.

CAUSE

This behavior can occur because the Windows File Protection (WFP) feature in Windows 2000 stores copies of system files in the Dllcache folder on the boot volume.

STATUS

This behavior is by design.

MORE INFORMATION

WFP prevents shared system files from being overwritten by non-operating system installation programs. By preventing the replacement of essential system files, file version mismatches can be avoided. WFP runs in the background on a Windows 2000 system.

Windows 2000 maintains backup (cached) versions of all these files in the Dllcache folder. The limit of the space that the cache uses is specified in the following registry key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon\SFCQuota

If FFFFFFFF is specified, all system files are cached in the Dllcache folder. WFP adds files to the cache until the size of the Dllcache folder reaches the SFCQuota value, or until the free space on the volume is 150 MB or less. All .sys, .dll, .exe, and .ocx files that are included on the Windows 2000 CD-ROM are protected. True-type fonts Micros.ttf, Tahoma.ttf, and Tahomabd.ttf are also protected.

You can change the size of the Dllcache folder by typing the following command at a command prompt

sfc /cachesize=xx

where xx represents the maximum size in MB for the Dllcache folder. Also, after restarting:

Sfc /purgecache

This deletes the current cache and allows SFC to rebuild the DllCache to the specified size.

For additional information about WFP and other improvements in Windows 2000, refer to the following Microsoft Web site:

http://www.microsoft.com/Windows/server/eval/strategic/relavail.asp

For additional information, click the article numbers below to view the articles in the Microsoft Knowledge Base:

222473 Registry Settings for Windows File Protection

222193 Description of the Windows 2000 Windows File Protection Feature

Modification Type:MajorLast Reviewed:11/13/2003
Keywords:kbenv kbprb kbWFP w2000wfp KB244861
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