UAC File Virtualization (luafv) Service Defaults in Windows 7

Virtualizes file write failures to per-user locations.

Default Settings

Startup type:Automatic
Display name:UAC File Virtualization
Service name:luafv
Service type:filesys
Error control:normal
Group:FSFilter Virtualization
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\luafv

Default Behavior

UAC File Virtualization is a file system driver. In Windows 7 it is starting automatically on the operating system startup. If UAC File Virtualization fails to start, Windows 7 attempts to write the failure details into Event Log. Then Windows 7 startup should proceed and the user should be notified that the luafv service is not running because of the error.


UAC File Virtualization is unable to start, if the FltMgr service is stopped or disabled.

Restore Default Startup Configuration for UAC File Virtualization

1. Select your Windows 7 edition and service pack, and then click Download.

2. Save the Win7_luafv_Service_Startup.cmd file to a local storage device.

3. Run the saved file as an administrator.

4. Restart the computer.

The luafv service is using the luafv.sys file that is located in the %WinDir%\system32\drivers folder. If the file is changed, damaged or deleted, you can restore its original version from Windows 7 installation media.