Execute a external program

I want to open a external program (p.e. calc.exe), using program execute

i wrote this script:

#include "apdefap.h"
void OnClick(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)
{

ProgramExecute("C:\\Winnt\\system32\\calc.exe");//Return-Type: unsigned long int
}

but doesnt work, what is wrong?

please help me