Close service handle

1. Do you need to call MyService.ServiceHandle.Close() manually?

No, you should not manually call MyService.ServiceHandle.Close() if you're using the ServiceController properly via Using or Dispose. The ServiceController class wraps the native service handle internally using a SafeHandle, and Dispose() (or the Using block) will automatically call ServiceHandle.Close() when the object is disposed. Manually calling ServiceHandle.Close() before the ServiceController is disposed is not recommended — doing so can leave the controller in an invalid state, potentially throwing an exception on further use. Let Using or Dispose handle it.

Using MyService As New ServiceController("BlahService")
    ' Use MyService here safely
End Using
' Disposes and closes handle cleanly

2. Calling MyService.Close() manually?

You generally don’t need to call MyService.Close() inside a Using block. Close() is called by Dispose() internally, and Using ensures disposal. Only call Close() if you are not using Using, and you're managing the object lifetime manually. Even in that case, calling Dispose() is clearer and preferred (MyService.Dispose()).

3. Should you use SafeHandle.Close() directly?

No. SafeHandle.Close() is available, but it's not recommended for normal application code to call directly — it's intended for use by classes like ServiceController that own the handle lifecycle.

4. About ChangeServiceConfig and the IntPtr

Your interop declaration looks fine, assuming you're doing low-level WinAPI P/Invoke work to configure services. Here's the signature clarified:

<DllImport("advapi32.dll", SetLastError:=True, CharSet:=CharSet.Unicode)>
Private Shared Function ChangeServiceConfig(
    <[In]> ByVal hService As IntPtr,
    ByVal dwServiceType As UInteger,
    ByVal dwStartType As UInteger,
    ByVal dwErrorControl As UInteger,
    ByVal lpBinaryPathName As String,
    ByVal lpLoadOrderGroup As String,
    ByRef lpdwTagId As UInteger,
    ByVal lpDependencies As String,
    ByVal lpServiceStartName As String,
    ByVal lpPassword As String,
    ByVal lpDisplayName As String
) As <MarshalAs(UnmanagedType.Bool)> Boolean
End Function

Make sure though that you're passing a valid, open hService (e.g., from OpenService) and you're using CloseServiceHandle properly after you're done (but only on handles from raw WinAPI, not ServiceController.ServiceHandle).

If the above response helps answer your question, remember to "Accept Answer" so that others in the community facing similar issues can easily find the solution. Your contribution is highly appreciated.

hth

Marcin