Cannot Start The Driver Service On Http Localhost Selenium Firefox C File

static void Main()

pkill -f geckodriver

Introduction If you are automating Firefox using Selenium WebDriver in C# (or any .NET language), you have likely encountered the dreaded WebDriverException : "Cannot start the driver service on http://localhost..." This error stops your automation dead in its tracks. It means Selenium cannot communicate with the geckodriver (the bridge between your code and Firefox). static void Main() pkill -f geckodriver Introduction If

foreach (var process in Process.GetProcessesByName("geckodriver")) process.Kill(); Force a specific, free port to avoid conflicts. service = FirefoxDriverService

service = FirefoxDriverService.CreateDefaultService(); service.LogPath = "geckodriver.log"; service.LogLevel = FirefoxDriverLogLevel.Trace; var driver = new FirefoxDriver(service); Check geckodriver.log – it will show port binding failures, binary issues, or profile problems. using OpenQA.Selenium.Firefox; class Program GitHub mozilla/geckodriver 4

// No need to set driver path anymore var driver = new FirefoxDriver(); // Selenium Manager handles geckodriver Update your NuGet packages to Selenium.WebDriver 4.6 or higher. Let me know in the comments which fix worked for you, or share your geckodriver.log for more help!

GitHub mozilla/geckodriver 4. Add Driver Path to System PATH (or specify explicitly) Option A – Add to PATH: Place geckodriver.exe in a folder already on PATH, or add its folder to system environment variables.