Disk Defragmenter (defragsvc) Service Defaults in Windows 7

Provides Disk Defragmentation Capabilities.

Default Settings

Startup type:Manual
Display name:Disk Defragmenter
Service name:defragsvc
Service type:own
Error control:normal
Path:%SystemRoot%\system32\svchost.exe -k defragsvc
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\defragsvc
  • SeChangeNotifyPrivilege
  • SeImpersonatePrivilege
  • SeIncreaseWorkingSetPrivilege
  • SeTcbPrivilege
  • SeSystemProfilePrivilege
  • SeAuditPrivilege
  • SeCreateGlobalPrivilege
  • SeBackupPrivilege
  • SeManageVolumePrivilege

Default Behavior

Disk Defragmenter is a Win32 service. In Windows 7 it won't be started if the user doesn't start it. When the Disk Defragmenter service is started, it is running as localSystem in its own process of svchost.exe. If Disk Defragmenter 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 defragsvc service is not running because of the error.


Disk Defragmenter is unable to start, if the Remote Procedure Call (RPC) service is stopped or disabled.

Restore Default Startup Configuration for Disk Defragmenter

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

2. Save the Win7_defragsvc_Service_Startup.cmd file to a local storage device.

3. Run the saved file as an administrator.

4. Restart the computer.

The defragsvc service is using the defragsvc.dll file that is located in the %WinDir%\System32 folder. If the file is changed, damaged or deleted, you can restore its original version from Windows 7 installation media.