Initiates a shutdown of the WinGate engine from the WinGate Management Console
The parent window of the message dialog that will appear as part of the shutdown
The bit flags that control the shutdown process
|SHUTDOWN_FLAG_RESTART||Restart the WinGate engine after it has shut down|
|SHUTDOWN_FLAG_NOCANCEL||Set if you don't wish to allow the user to cancel the shutdown|
|SHUTDOWN_FLAG_ASKUSER||Prompt the user for verification that they wish to shutdown|
If the shutdown request succeeds then the return value is ERROR_SUCCESS.