Diagnostic System Host - Windows 11 Service
The Diagnostic System Host is used by the Diagnostic Policy Service to host diagnostics that need to run in a Local System context. If this service is stopped, any diagnostics that depend on it will no longer function.
This service also exists in Windows 10, 7, 8 and Vista.
Startup Type
| Windows 11 version | Home | Pro | Education | Enterprise |
|---|---|---|---|---|
| 21H2 | Manual | Manual | Manual | Manual |
| 22H2 | Manual | Manual | Manual | Manual |
| 23H2 | Manual | Manual | Manual | Manual |
| 24H2 | Manual | Manual | Manual | Manual |
Default Properties
| Display name: | Diagnostic System Host |
| Service name: | WdiSystemHost |
| Type: | share |
| Path: | %WinDir%\System32\svchost.exe -k LocalSystemNetworkRestricted -p |
| File: | %WinDir%\system32\wdi.dll |
| Error control: | normal |
| Object: | LocalSystem |
| Privileges: |
|
Default Behavior
The Diagnostic System Host service is running as LocalSystem in a shared process of svchost.exe. Other services might run in the same process. If Diagnostic System Host fails to start, the error is logged. Windows 11 startup proceeds, but a message box is displayed informing you that the WdiSystemHost service has failed to start.
Restore Default Startup Type for Diagnostic System Host
Automated Restore
1. Select your Windows 11 edition and release, and then click on the Download button below.
2. Save the RestoreDiagnosticSystemHostWindows11.bat file to any folder on a local drive such as SSD or a hard disk.
3. Right-click the downloaded batch file and select Properties.
4. Check the Unblock checkbox and click OK.
5. Right-click the batch file again and select Run as administrator.
6. Restart the computer to save changes.
Note. Make sure that the wdi.dll file exists in the %WinDir%\system32 folder. If this file is missing you can try to restore it from your Windows 11 installation media.