public static uint LaunchProcessAsUser(string cmdLine, IntPtr token, IntPtr envBlock)
        {
            bool result = false;

            PROCESS_INFORMATION pi = new PROCESS_INFORMATION();
            SECURITY_ATTRIBUTES saProcess = new SECURITY_ATTRIBUTES();
            SECURITY_ATTRIBUTES saThread = new SECURITY_ATTRIBUTES();
            saProcess.nLength = (uint)Marshal.SizeOf(saProcess);
            saThread.nLength = (uint)Marshal.SizeOf(saThread);

            STARTUPINFO si = new STARTUPINFO();
            si.cb = (uint)Marshal.SizeOf(si);

            si.lpDesktop = @"WinSta0\Default"; //Modify as needed
            si.dwFlags = ProcessAsUser.STARTF_USESHOWWINDOW | ProcessAsUser.STARTF_FORCEONFEEDBACK;
            si.wShowWindow = ProcessAsUser.SW_SHOW;
            //Set other si properties as required.

            result = ProcessAsUser.CreateProcessAsUser(
                token,
                null,
                cmdLine,
                ref saProcess,
                ref saThread,
                false,
                ProcessAsUser.CREATE_UNICODE_ENVIRONMENT,
                envBlock,
                null,
                ref si,
                out pi);

            if (result == false)
            {
                int error = Marshal.GetLastWin32Error();
                string message = String.Format("CreateProcessAsUser Error: {0}", error);
                Debug.WriteLine(message);

            }

            return result ? pi.dwProcessId : uint.MaxValue;
        }
 public static extern bool CreateProcessAsUser(
     IntPtr hToken,
     string lpApplicationName,
     string lpCommandLine,
     ref SECURITY_ATTRIBUTES lpProcessAttributes,
     ref SECURITY_ATTRIBUTES lpThreadAttributes,
     bool bInheritHandles,
     uint dwCreationFlags,
     IntPtr lpEnvironment,
     string lpCurrentDirectory,
     ref STARTUPINFO lpStartupInfo,
     out PROCESS_INFORMATION lpProcessInformation);
        public static uint LaunchProcessAsUserPid(string cmdLine, IntPtr token, IntPtr envBlock)
        {
            bool result = false;

            PROCESS_INFORMATION pi = new PROCESS_INFORMATION();
            SECURITY_ATTRIBUTES saProcess = new SECURITY_ATTRIBUTES();
            SECURITY_ATTRIBUTES saThread = new SECURITY_ATTRIBUTES();
            saProcess.nLength = (uint)Marshal.SizeOf(saProcess);
            saThread.nLength = (uint)Marshal.SizeOf(saThread);

            STARTUPINFO si = new STARTUPINFO();
            si.cb = (uint)Marshal.SizeOf(si);

            //if this member is NULL, the new process inherits the desktop
            //and window station of its parent process. If this member is
            //an empty string, the process does not inherit the desktop and
            //window station of its parent process; instead, the system
            //determines if a new desktop and window station need to be created.
            //If the impersonated user already has a desktop, the system uses the
            //existing desktop.

            si.lpDesktop = @"WinSta0\Default"; //Modify as needed
            si.dwFlags = STARTF_USESHOWWINDOW | STARTF_FORCEONFEEDBACK;
            si.wShowWindow = SW_SHOW;
            //Set other si properties as required.

            result = CreateProcessAsUser(
                token,
                null,
                cmdLine,
                ref saProcess,
                ref saThread,
                false,
                CREATE_UNICODE_ENVIRONMENT,
                envBlock,
                null,
                ref si,
                out pi);

            if (result == false)
            {
                int error = Marshal.GetLastWin32Error();
                string message = String.Format("CreateProcessAsUser Error: {0}", error);
                Debug.WriteLine(message);

            }

            return result ? pi.dwProcessId : uint.MaxValue;
        }