Add documentation for SessionNotCreatedException in troubleshooting errors

Author: yvsvarma

website_and_docs/content/documentation/webdriver/troubleshooting/errors/_index.en.md

@@ -145,3 +145,21 @@ like when the last tab/browser has closed (e.g. `driver.close()`)
 
 Check your script for instances of `driver.close()` and `driver.quit()`, and any other possible causes 
 of closed tabs/browsers. It could be that you are locating an element before you should/can.
+
+## SessionNotCreatedException
+
+This exception occurs when the WebDriver is unable to create a new session for the browser. This often happens due to version mismatches, system-level restrictions, or configuration issues.
+
+### Likely Cause
+
+- The browser version and WebDriver version are incompatible (e.g., ChromeDriver v113 with Chrome v115).
+- macOS privacy settings may block the WebDriver from running.
+- The WebDriver binary is missing, inaccessible, or lacks the necessary execution permissions (e.g., on Linux/macOS, the driver file may not be executable).
+
+
+### Possible Solutions
+
+- Ensure the WebDriver version matches the browser version. For Chrome, check the browser version at `chrome://settings/help` and download the matching driver from [ChromeDriver Downloads](https://chromedriver.chromium.org/downloads).
+- On macOS, go to **System Settings > Privacy & Security**, and allow the driver to run if blocked.
+- Verify the driver binary is executable (`chmod +x /path/to/driver` on Linux/macOS).
+