MATLAB's search path

I deploy Matpower to a dll file, and I invoke it in C#.

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
using MatPower;
using MathWorks.MATLAB.NET.Arrays;
using MathWorks.MATLAB.NET.Utility;
namespace ForTest
{
    class Program
    {
        static void Main(string[] args)
        {
            mPowerFlow m_pf = new mPowerFlow();
            string strCmd = @"D:\case9.m";
            m_pf.runpf(strCmd);
        }
    }
}

But get some errors.

So, could anyone tell me the problem?

Also, does the matlab's search paths work as the same when I invoke a dll in C#?