geckodriver.exe not in current directory or path variable, Selenium 2.53.1 + Firefox 48 + Selenium 3 Beta
Try to put the geckodriver.exe in your path: C:\Users\YourName\Documents\Visual Studio 2013\Projects\seleniump\seleniump\bin\Debug
you can find geckodriver.exe at this link:
Install the Selenium.Firefox.Webdriver NuGet package.
This will copy geckodriver.exe to the bin folder.
This solution may helps you fix problem: ( It did help me though)
public class TestResult { private IWebDriver driver; private StringBuilder verificationErrors; private string baseURL; private bool acceptNextAlert = true; [TestInitialize] public void SetupTest() { FirefoxDriverService service = FirefoxDriverService.CreateDefaultService(@"C:\geckodriver", "geckodriver.exe"); service.Port = 64444; service.FirefoxBinaryPath = @"C:\Program Files (x86)\Firefox Developer Edition\firefox.exe"; driver = new FirefoxDriver(service); baseURL = "http://localhost:49539"; verificationErrors = new StringBuilder(); }}