Diagnostic Service Host (WdiServiceHost) Defaults in Windows 10

The Diagnostic Service Host is used by the Diagnostic Policy Service to host diagnostics that need to run in a Local Service context. If this service is stopped, any diagnostics that depend on it will no longer function.

Default Settings

Startup type:Manual
Display name:Diagnostic Service Host
Service name:WdiServiceHost
Service type:share
Error control:normal
Object:NT AUTHORITY\LocalService
Path:%SystemRoot%\System32\svchost.exe -k LocalService
File:%SystemRoot%\system32\wdi.dll
Registry key:HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\WdiServiceHost
Privileges:
  • SeChangeNotifyPrivilege
  • SeImpersonatePrivilege
  • SeSystemProfilePrivilege

Default Behavior

Diagnostic Service Host is a Win32 service. In Windows 10 it is starting only if the user, an application or another service starts it. When the Diagnostic Service Host is started, it is running as NT AUTHORITY\LocalService in a shared process of svchost.exe along with other services. If Diagnostic Service Host fails to start, the failure details are being recorded into Event Log. Then Windows 10 will start up and notify the user that the WdiServiceHost service has failed to start due to the error.

Restore Default Startup Configuration for Diagnostic Service Host

1. Select your Windows 10 edition and release, and then click Download.

2. Save the Win10_WdiServiceHost_Service_Startup.cmd file to a local storage device.

3. Run the saved file as an administrator.

4. Restart the computer.

The WdiServiceHost service is using the wdi.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 10 installation media.