Cannot Start The Driver Service On Http Localhost Selenium Firefox C __full__ -

This is the culprit in 80% of cases. You cannot use arbitrary versions of Selenium, GeckoDriver, and Firefox. They speak a specific protocol. If the versions don't align, GeckoDriver starts (you might see a flash of a console window) and then immediately crashes, taking the localhost service down with it.

The WebDriverManager checks your installed Firefox version, finds the matching geckodriver.exe , downloads it to a temporary cache, and points Selenium to it automatically. This eliminates the "Cannot start driver service" error caused by missing files or path issues 99% of the time. This is the culprit in 80% of cases

Great for servers or background tasks.

gecko_path = r'C:\WebDrivers\geckodriver.exe' finds the matching geckodriver.exe