System Data Oledb C# by API

using System;
using System.Data;
using System.Data.SqlClient;
using System.Data.OleDb;
class MainClass
{
  static void Main(string[] args)
  {
        string ConnectionString = @"Provider=Microsoft.Jet.OLEDB.4.0; Data Source=c:\Northwind.mdb";
        OleDbConnection conn = new OleDbConnection(ConnectionString);       
        
        conn.Open();
        conn.Close();
        OleDbConnection.ReleaseObjectPool();
  }
}