Windows File Protection: Difference between revisions

Revision as of 21:59, 17 June 2008

Latest revision as of 10:31, 3 July 2025

(32 intermediate revisions by 27 users not shown)

Line 1:

{{Short description|Microsoft Windows security sub-system}}

'''Windows File Protection''' (WFP) is a technology included in all [[Microsoft Windows]] [[operating system]]s beginning with [[Windows 2000]] to prevent programs from replacing critical Windows system files. Protecting core system files prevents problems such as [[DLL hell]] with programs and the operating system. Windows 2000, [[Windows XP]] and [[Windows Server 2003]] include it under the name of ''Windows File Protection''; [[Windows Me]] includes it as ''System File Protection''.

{{Multiple issues|

{{more footnotes|date=October 2015}}

{{Outdated|date=June 2025}}

}}

'''Windows File Protection''' ('''WFP'''), a sub-system included in [[Microsoft Windows]] [[operating system]]s of the [[Windows 2000]] and [[Windows XP]] era, aims to prevent programs from replacing critical Windows [[system file]]s.<ref name="h795">{{cite book |url=https://books.google.com/books?id=krByP88msCwC&pg=PA99 |title=Configuring Windows 2000 without Active Directory |publisher=Syngress |year=2001 |isbn=978-0-08-047672-8 |pages=99–105 |access-date=2025-03-01}}</ref><ref name="c359">{{cite book |last=Carvey |first=H. |url=https://books.google.com/books?id=rsdAX92FWBgC&pg=PA180 |title=Windows Forensic Analysis Toolkit: Advanced Analysis Techniques for Windows 7 |publisher=Syngress |year=2012 |isbn=978-1-59749-728-2 |page=180 |access-date=2025-03-01}}</ref><ref name="b652">{{cite book |last=Hart-Davis |first=G. |url=https://books.google.com/books?id=Fy8_GF42WCIC&pg=PA439 |title=Mastering Windows XP Home Edition |publisher=Wiley |year=2006 |isbn=978-0-7821-5059-9 |page=439 |access-date=2025-03-01}}</ref> Protecting core system files mitigates problems such as [[DLL hell]] with programs and the operating system. Windows 2000, [[Windows XP]] and [[Windows Server 2003]] include WFP under the name of ''Windows File Protection''; [[Windows Me]] includes it as '''System File Protection''' ('''SFP''').

When Windows File Protection is active, replacing or deleting a system file that has no [[file lock]] to prevent it from being overwritten causes Windows to immediately and silently restore the original copy of the file. The original version of the file is restored from a cached folder which contains backup copies of these files. For the Windows NT family, the cached folder is located at <tt>%WinDir%\System32\Dllcache</tt>. Windows Me caches its entire set of compressed cabinet setup files and stores them in the <tt>%Systemroot%\Options\Install</tt> folder.

== Operation ==

All files which are installed by the operating system (such as <tt>DLL</tt>, <tt>EXE</tt>, <tt>SYS</tt>, <tt>OCX</tt> etc.) are protected from deletion or being replaced by older versions. The [[digital signature]]s of these files are checked using [[code signing]] and the signature catalog files stored in the <tt>%Systemroot%\system32\catRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE}</tt> folder. Only certain operating system components such as the ''Package Installer'' (Update.exe) or [[Windows Installer]] (Msiexec.exe) can replace these files. Changes made using any other methods in order to replace these files are reverted and the files are silently restored from the cache. If Windows File Protection cannot automatically find the file in the cached folder, it searches the network path or prompts the user for the Windows installation disc to restore the appropriate version of the file.

WhenWith Windows File Protection is active, replacing or deleting a system file that has no [[File locking|file lock]] to prevent it from beinggetting overwritten causes Windows to immediately and silently to restore the original copy of the file. The original version of the file is restored from a cached folder which contains backup copies of these files. For theThe [[Windows NT]] family, uses the cached folder is located at <tt>{{mono|%WinDirSystemRoot%\System32\Dllcache</tt>}}. [[Windows Me]] caches its entire set of compressed cabinet setup files and stores them in the <tt>{{mono|%Systemrootwindir%\Options\Install</tt>}} folder.

AllWFP covers all files which are installed by the operating system installs (such as <tt>{{mono|DLL</tt>}}, <tt>{{mono|EXE</tt>}}, <tt>{{mono|SYS</tt>}}, <tt>{{mono|OCX</tt>}} etc.), are protectedprotecting them from deletion or beingfrom replacedreplacement by older versions. The [[digital signature]]s of these files are checked using [[code signing]] and the signature catalog files stored in the <tt>{{mono|%SystemrootSystemRoot%\system32\catRootCatRoot\{F750E6C3-38EE-11D1-85E5-00C04FC295EE}</tt>}} folder. Only certain operating system components such as the ''Package Installer'' (Update.exe) or [[Windows Installer]] (Msiexec.exe) can replace these files. Changes made using any other methods in order to replace these files are reverted and the files are silently restored from the cache. If Windows File Protection cannot automatically find the file in the cached folder, it searches the network path or prompts the user for the Windows installation disc to restore the appropriate version of the file.

[[Windows Vista]] does not include Windows File Protection, but it includes [[Windows Resource Protection]] which protects files using [[Access control list|ACLs]]. Windows Resource Protection aims to protect core [[Windows registry|registry]] keys and values and prevent potentially damaging system configuration changes, besides operating system files.

WFP integrates with the [[System File Checker]] ({{mono|sfc.exe}}) utility.

== See also ==

*[[Windows Resource Protection]]

[[Windows Vista]] doesand later Windows systems do not include Windows File Protection, but itthey includesinclude [[Windows Resource Protection]] which protects files using [[Access control list|ACLs]]. Windows Resource Protection aims to protect core [[Windows registry|registry]] keys and values and prevent potentially damaging system configuration changes, besides operating system files.

*[[System File Checker]]

*[[Access Control List]]

The non-use of ACLs in Windows File Protection was a design choice: Not only did it allow operation on non-NTFS systems, but it prevented those same "bad" installers from failing completely from a file access error.

*[[Security Identifier]]

== References ==

{{Reflist}}

== External links ==

Line 18 ⟶ 26:

* [http://www.microsoft.com/whdc/archive/wfp.mspx Whitepaper on Windows File Protection]

* [http://support.microsoft.com/kb/253571 Overview of System File Protection (Windows Me)]

* [httphttps://wwwweb.archive.org/web/20160321062438/https://bitsum.com/aboutwfp.asp Hacking Windows File Protection]

* [https://filehare.com/download-protected-folder/ Effective Files Protection Tool]

{{Windows Components}}

[[Category:MicrosoftDiscontinued Windows components]]

[[Category:Windows administration]]

[[Category:Windows components]]