Sfc

Updated: April 17, 2012

Applies To: Windows Server 2008, Windows Server 2008 R2, Windows Server 2008 R2 with SP1, Windows Vista

Scans and verifies the integrity of all protected system files and replaces incorrect versions with correct versions.

For examples of how to use this command, see Examples.

Syntax

sfc [/scannow] [/verifyonly] [/scanfile=<file>] [/verifyfile=<file>] [/offwindir=<offline windows directory> /offbootdir=<offline boot directory>]

Parameters

Parameter Description

/scannow

Scans the integrity of all protected system files and repairs files with problems when possible.

/verifyonly

Scans integrity of all protected system files. No repair operation is performed.

/scanfile

Scans integrity of the specified file and repairs the file if problems are detected, when possible.

<file>

Specified full path and filename

/verifyfile

Verifies the integrity of the specified file. No repair operation is performed.

/offwindir

Specifies the location of the offline windows directory, for offline repair.

/offbootdir

Specifies the location of the offline boot directory for offline

/?

Displays Help at the command prompt.

Remarks

  • You must be logged on as a member of the Administrators group to run sfc.exe.

  • If sfc discovers that a protected file has been overwritten, it retrieves the correct version of the file from the systemroot\system32\dllcache folder, and then replaces the incorrect file.

  • There are functional differences between sfc on Windows Server® 2003, Windows Server® 2008, and Windows Server® 2008 R2:

  • For more information about sfc on Windows Server 2003, see article 310747 in the Microsoft Knowledge Base.

  • For more information about sfc on Windows Server® 2008, and Windows Server® 2008 R2, see System File Checker.

Examples

To verify the kernel32.dll file, type:

sfc /verifyfile=c:\windows\system32\kernel32.dll

To setup offline repair of the kernel32.dll file with an offline boot directory set to d: and offline windows directory set to d:\windows, type:

sfc /scanfile=d:\windows\system32\kernel32.dll /offbootdir=d:\ /offwindir=d:\windows

Additional references