title: How to fix WebDriverException: The browser appears to have exited before we could connect?
body: <p>In my Linux system I use Firefox, execute my program, the error which I've is:</p>
  
  <pre><code>Traceback (most recent call last):
  
  File "shenma_diff_main_v2.py", line 90, in &lt;module&gt;
      browser = webdriver.Firefox(profile)
    File "/usr/local/lib/python2.7/site-packages/selenium/webdriver/firefox/webdriver.py", line 59, in __init__
      self.binary, timeout),
    File "/usr/local/lib/python2.7/site-packages/selenium/webdriver/firefox/extension_connection.py", line 47, in __init__
      self.binary.launch_browser(self.profile)
    File "/usr/local/lib/python2.7/site-packages/selenium/webdriver/firefox/firefox_binary.py", line 66, in launch_browser
      self._wait_until_connectable()
    File "/usr/local/lib/python2.7/site-packages/selenium/webdriver/firefox/firefox_binary.py", line 100, in _wait_until_connectable
      raise WebDriverException("The browser appears to have exited "
  selenium.common.exceptions.WebDriverException: Message: The browser appears to have exited before we could connect. If you specified a log_file in the FirefoxBinary constructor, check it for details.
  </code></pre>
  
  <p>If I use root execute my program is OK.</p>