title: Empty error message in Selenium WebDriverException
body: <p>I am attempting to use Selenium/BeautifulSoup to unit test a web page. I am getting an error though that I haven't been able to Google.</p>
  
  <p><code>selenium.common.exceptions.WebDriverException: Message: ''</code></p>
  
  <p>I am using a Portable version of Firefox and a proxy.</p>
  
  <pre><code>import urllib2
  from bs4 import BeautifulSoup
  from selenium import webdriver
  from selenium.webdriver.common.by import By
  from selenium.webdriver.support.ui import Select
  from selenium.common.exceptions import NoSuchElementException
  import time
  import sys
  
  def getItemDivs(url):
      profile = webdriver.FirefoxProfile()
      profile.set_preference("general.useragent.override","Mozilla/5.0 (Windows NT 6.1; WOW64; rv:12.0) Gecko/20100101 Firefox/21.0")
      profile.set_preference("network.proxy.http", "proxy.example.com")
  
      ffbin = webdriver.firefox.firefox_binary.FirefoxBinary('C:\\FirefoxPortable\\App\\Firefox\\firefox.exe')
  
      # IT FAILS ON THE NEXT LINE
      driver=webdriver.Firefox(profile, firefox_binary=ffbin)
      driver.implicitly_wait(30)
  
      # THIS LINE CONTAINS A VALID COOKIE, BUT IT HAS BEEN REMOVED FOR THIS QUESTION.
      driver.add_cookie(&lt;&lt;mycookie&gt;&gt;)
      base_url = url
      verificationErrors = []
      accept_next_alert = True
  
      driver.get(base_url)
      scrap1 = driver.page_source
      soup = BeautifulSoup(scrap1)
  </code></pre>
  
  <p>This question is similar to <a href="https://stackoverflow.com/questions/8470193/selenium-fails-with-empty-exception-message">this one</a>, however, in that question they had a successful first request. I haven't had a success.</p>
  
  <p>What can cause this type of exception but leave the message empty?</p>