title: selenium.common.exceptions.SessionNotCreatedException: Message: Unable to create new service: OperaDriverService
body: <p>OS: Ubuntu</p>
  
  <p>I am following <a href="http://selenium-python.readthedocs.io/getting-started.html#using-selenium-with-remote-webdriver" rel="nofollow noreferrer">step 2.5 of this tutorial</a>:</p>
  
  <p>1) I downloaded selenium server standalone of two versions:<code>selenium-server-standalone-2.50.1.jar</code> and <code>selenium-server-standalone-3.13.0.jar</code>.</p>
  
  <p>2) I created a file named test_selenium_server.py:</p>
  
  <pre><code>from selenium import webdriver
  from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
  
  driver = webdriver.Remote(
     command_executor='http://127.0.0.1:4444/wd/hub',
     desired_capabilities=DesiredCapabilities.CHROME)
  
  driver = webdriver.Remote(
     command_executor='http://127.0.0.1:4444/wd/hub',
     desired_capabilities=DesiredCapabilities.OPERA)
  
  driver = webdriver.Remote(
     command_executor='http://127.0.0.1:4444/wd/hub',
     desired_capabilities=DesiredCapabilities.HTMLUNITWITHJS)
  </code></pre>
  
  <p>I installed chromedriver and geckodriver.</p>
  
  <p>When I run <code>java -jar selenium-server-standalone-2.50.1.jar</code> and then <code>python test_selenium_server.py</code>, I get an error like:</p>
  
  <pre><code>Traceback (most recent call last):
    File "test_selenium_server.py", line 12, in &lt;module&gt;
      desired_capabilities=DesiredCapabilities.OPERA)
  ...
  selenium.common.exceptions.WebDriverException: Message: The best matching driver provider org.openqa.selenium.htmlunit.HtmlUnitDriver can't create a new driver instance for Capabilities [{browserName=opera, version=, platform=ANY}]
  Build info: version: '2.50.1', revision: 'd7fc91b', time: '2016-01-29 19:08:26'
  System info: host: 'AMDC2763', ip: '127.0.1.1', os.name: 'Linux', os.arch: 'amd64', os.version: '4.15.0-30-generic', java.version: '1.8.0_181'
  Driver info: driver.version: unknown
  ...
  </code></pre>
  
  <p>And when I run <code>java -jar selenium-server-standalone-3.13.0.jar</code> and then <code>python test_selenium_server.py</code>, I get an error like:</p>
  
  <pre><code>Traceback (most recent call last):
    File "test_selenium_server.py", line 12, in &lt;module&gt;
      desired_capabilities=DesiredCapabilities.OPERA)
  ...
  selenium.common.exceptions.SessionNotCreatedException: Message: Unable to create new service: OperaDriverService
  Build info: version: '3.13.0', revision: '2f0d292', time: '2018-06-25T15:32:19.891Z'
  System info: host: 'AMDC2763', ip: '127.0.1.1', os.name: 'Linux', os.arch: 'amd64', os.version: '4.15.0-30-generic', java.version: '1.8.0_181'
  Driver info: driver.version: unknown
  ...
  </code></pre>
  
  <p>I've tried both python2 and python3 (they give the same errors) and searched through half the Internet, but found nothing. I believe that there is one problem that is causing those errors, that is why I showed both of error messages here. Help please.</p>
  
  <p><strong>EDIT:</strong> On MacOS High Sierra, I am getting the same errors.</p>