ScreenshotsTests.cs

[Test]
public void TakingWebDriverScreenshot()
{
    using (var driver = new InternetExplorerDriver())
    {
        driver.Navigate().GoToUrl(@"https://automatetheplanet.com");
        var screenshot = ((ITakesScreenshot)driver).GetScreenshot();
        var tempFilePath = Path.GetTempFileName().Replace(".tmp", ".png");
        screenshot.SaveAsFile(tempFilePath, ScreenshotImageFormat.Png);
    }
}