donet Selenium报错

Question

using System;
using OpenQA.Selenium;
using OpenQA.Selenium.IE;

namespace SeleniumDemo
{
    class Program
    {
        static void Main(string[] args)
        {
            IWebDriver driver = new InternetExplorerDriver();
            driver.Manage().Timeouts().ImplicitlyWait(new TimeSpan(0, 0, 10));

            driver.Navigate().GoToUrl("http://www.baidu.com");
            System.Threading.Thread.Sleep(5000);
            Console.WriteLine(driver.PageSource);
            //driver.FindElement(By.Id("kw")).SendKeys("Selenium");
            //driver.FindElement(By.Id("su")).Click();

            driver.Quit();
        }
    }
}

以上代码是网上抄来的，Selenium SDK也已经引入到项目，IEDriverServer也放到项目下了。run后可见IE会打开百度，但driver取不到内容，会报错：

An unhandled exception of type 'OpenQA.Selenium.NoSuchWindowException' occurred in WebDriver.dll

Additional information: Unable to get browser

那里出问题了？