Diagnostic System Host - Windows Vista Service
The Diagnostic System Host service enables problem detection, troubleshooting and resolution for Windows components. If this service is stopped, some diagnostics will no longer function. If this service is disabled, any services that explicitly depend on it will fail to start.
This service also exists in Windows 10, 11, 7 and 8.
Startup Type
| Windows Vista edition | without SP | SP1 | SP2 |
|---|---|---|---|
| Starter | Manual | Manual | Manual |
| Home Basic | Manual | Manual | Manual |
| Home Premium | Manual | Manual | Manual |
| Business | Manual | Manual | Manual |
| Ultimate | Manual | Manual | Manual |
Default Properties
| Display name: | Diagnostic System Host |
| Service name: | WdiSystemHost |
| Type: | share |
| Path: | %WinDir%\System32\svchost.exe -k LocalSystemNetworkRestricted |
| File: | %WinDir%\system32\wdi.dll |
| Error control: | normal |
| Object: | LocalSystem |
| Privileges: |
|
Default Behavior
The Diagnostic System Host service starts as LocalSystem and runs in a shared process of svchost.exe. If Diagnostic System Host fails to start, the error is recorded into the Event Log. Windows Vista startup proceeds, but a message box is displayed informing you that the WdiSystemHost service has failed to start.
Restore Default Startup Type of Diagnostic System Host
Automated Restore
1. Select your Windows Vista edition and Service Pack, and then click on the Download button below.
2. Save the RestoreDiagnosticSystemHostWindowsVista.bat file to any folder on your hard drive.
3. Right-click the downloaded batch file and select Run as administrator.
4. 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 Vista installation media.