title: The path to the driver executable must be set by the webdriver.chrome.driver system property (php)
body: <p>I'm having a problems with running my php selenium test. I just switched to Ubuntu os and now i'm getting this exception stack trance on selenium server.</p>
  
  <p>Selenium server</p>
  
  <pre><code> 08:58:49.965 INFO - Launching a standalone Selenium Server
      08:58:49.986 INFO - Java: Oracle Corporation 25.101-b13
      08:58:49.986 INFO - OS: Linux 4.4.0-36-generic amd64
      08:58:49.996 INFO - v2.53.0, with Core v2.53.0. Built from revision 35ae25b
      08:58:50.040 INFO - Driver provider org.openqa.selenium.ie.InternetExplorerDriver registration is skipped:
      registration capabilities Capabilities [{ensureCleanSession=true, browserName=internet explorer, version=, platform=WINDOWS}] does not match the current platform LINUX
      08:58:50.041 INFO - Driver provider org.openqa.selenium.edge.EdgeDriver registration is skipped:
      registration capabilities Capabilities [{browserName=MicrosoftEdge, version=, platform=WINDOWS}] does not match the current platform LINUX
      08:58:50.041 INFO - Driver class not found: com.opera.core.systems.OperaDriver
      08:58:50.041 INFO - Driver provider com.opera.core.systems.OperaDriver is not registered
      08:58:50.041 INFO - Driver provider org.openqa.selenium.safari.SafariDriver registration is skipped:
      registration capabilities Capabilities [{browserName=safari, version=, platform=MAC}] does not match the current platform LINUX
      08:58:50.042 INFO - Driver class not found: org.openqa.selenium.htmlunit.HtmlUnitDriver
      08:58:50.042 INFO - Driver provider org.openqa.selenium.htmlunit.HtmlUnitDriver is not registered
      08:58:50.075 INFO - RemoteWebDriver instances should connect to: http://127.0.0.1:4444/wd/hub
      08:58:50.075 INFO - Selenium Server is up and running
      08:59:41.556 INFO - Executing: [new session: Capabilities [{browserName=chrome, platform=LINUX}]])
      08:59:41.566 INFO - Creating a new session for Capabilities [{browserName=chrome, platform=LINUX}]
      08:59:41.573 WARN - Exception thrown
      java.util.concurrent.ExecutionException: org.openqa.selenium.WebDriverException: java.lang.reflect.InvocationTargetException
      Build info: version: '2.53.0', revision: '35ae25b', time: '2016-03-15 17:00:58'
      System info: host: 'Keson', ip: '127.0.1.1', os.name: 'Linux', os.arch: 'amd64', os.version: '4.4.0-36-generic', java.version: '1.8.0_101'
      Driver info: driver.version: unknown
          at java.util.concurrent.FutureTask.report(FutureTask.java:122)
          at java.util.concurrent.FutureTask.get(FutureTask.java:192)
          at org.openqa.selenium.remote.server.DefaultSession.execute(DefaultSession.java:183)
          at org.openqa.selenium.remote.server.DefaultSession.&lt;init&gt;(DefaultSession.java:119)
          at org.openqa.selenium.remote.server.DefaultSession.createSession(DefaultSession.java:95)
          at org.openqa.selenium.remote.server.DefaultDriverSessions.newSession(DefaultDriverSessions.java:124)
          at org.openqa.selenium.remote.server.handler.NewSession.handle(NewSession.java:59)
          at org.openqa.selenium.remote.server.handler.NewSession.handle(NewSession.java:1)
          at org.openqa.selenium.remote.server.rest.ResultConfig.handle(ResultConfig.java:111)
          at org.openqa.selenium.remote.server.JsonHttpCommandHandler.handleRequest(JsonHttpCommandHandler.java:79)
          at org.openqa.selenium.remote.server.DriverServlet.handleRequest(DriverServlet.java:204)
          at org.openqa.selenium.remote.server.DriverServlet.doPost(DriverServlet.java:166)
          at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)
          at org.openqa.selenium.remote.server.DriverServlet.service(DriverServlet.java:132)
          at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
          at org.openqa.jetty.jetty.servlet.ServletHolder.handle(ServletHolder.java:428)
          at org.openqa.jetty.jetty.servlet.ServletHandler.dispatch(ServletHandler.java:680)
          at org.openqa.jetty.jetty.servlet.ServletHandler.handle(ServletHandler.java:571)
          at org.openqa.jetty.http.HttpContext.handle(HttpContext.java:1526)
          at org.openqa.jetty.http.HttpContext.handle(HttpContext.java:1479)
          at org.openqa.jetty.http.HttpServer.service(HttpServer.java:920)
          at org.openqa.jetty.http.HttpConnection.service(HttpConnection.java:820)
          at org.openqa.jetty.http.HttpConnection.handleNext(HttpConnection.java:986)
          at org.openqa.jetty.http.HttpConnection.handle(HttpConnection.java:837)
          at org.openqa.jetty.http.SocketListener.handleConnection(SocketListener.java:243)
          at org.openqa.jetty.util.ThreadedServer.handle(ThreadedServer.java:358)
          at org.openqa.jetty.util.ThreadPool$PoolThread.run(ThreadPool.java:537)
      Caused by: org.openqa.selenium.WebDriverException: java.lang.reflect.InvocationTargetException
      Build info: version: '2.53.0', revision: '35ae25b', time: '2016-03-15 17:00:58'
      System info: host: 'Keson', ip: '127.0.1.1', os.name: 'Linux', os.arch: 'amd64', os.version: '4.4.0-36-generic', java.version: '1.8.0_101'
      Driver info: driver.version: unknown
          at org.openqa.selenium.remote.server.DefaultDriverProvider.callConstructor(DefaultDriverProvider.java:113)
          at org.openqa.selenium.remote.server.DefaultDriverProvider.newInstance(DefaultDriverProvider.java:97)
          at org.openqa.selenium.remote.server.DefaultDriverFactory.newInstance(DefaultDriverFactory.java:60)
          at org.openqa.selenium.remote.server.DefaultSession$BrowserCreator.call(DefaultSession.java:222)
          at org.openqa.selenium.remote.server.DefaultSession$BrowserCreator.call(DefaultSession.java:1)
          at java.util.concurrent.FutureTask.run(FutureTask.java:266)
          at org.openqa.selenium.remote.server.DefaultSession$1.run(DefaultSession.java:176)
          at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
          at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
          at java.lang.Thread.run(Thread.java:745)
      Caused by: java.lang.reflect.InvocationTargetException
          at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
          at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
          at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
          at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
          at org.openqa.selenium.remote.server.DefaultDriverProvider.callConstructor(DefaultDriverProvider.java:103)
          ... 9 more
      Caused by: java.lang.IllegalStateException: The path to the driver executable must be set by the webdriver.chrome.driver system property; for more information, see https://github.com/SeleniumHQ/selenium/wiki/ChromeDriver. The latest version can be downloaded from http://chromedriver.storage.googleapis.com/index.html
          at com.google.common.base.Preconditions.checkState(Preconditions.java:199)
          at org.openqa.selenium.remote.service.DriverService.findExecutable(DriverService.java:109)
          at org.openqa.selenium.chrome.ChromeDriverService.access$0(ChromeDriverService.java:1)
          at org.openqa.selenium.chrome.ChromeDriverService$Builder.findDefaultExecutable(ChromeDriverService.java:137)
          at org.openqa.selenium.remote.service.DriverService$Builder.build(DriverService.java:296)
          at org.openqa.selenium.chrome.ChromeDriverService.createDefaultService(ChromeDriverService.java:88)
          at org.openqa.selenium.chrome.ChromeDriver.&lt;init&gt;(ChromeDriver.java:138)
          ... 14 more
      08:59:41.576 WARN - Exception: The path to the driver executable must be set by the webdriver.chrome.driver system property; for more information, see https://github.com/SeleniumHQ/selenium/wiki/ChromeDriver. The latest version can be downloaded from http://chromedriver.storage.googleapis.com/index.html
  </code></pre>
  
  <p>Chromdriver is running</p>
  
  <pre><code>Starting ChromeDriver (v2.9.248304) on port 9515
  </code></pre>
  
  <p>And this is an error when i run the test</p>
  
  <pre><code>There was 1 error:
  UnknownServerException: The path to the driver executable must be set by the webdriver.chrome.driver system property; for more information, see https://github.com/SeleniumHQ/selenium/wiki/ChromeDriver. The latest version can be downloaded from http://chromedriver.storage.googleapis.com/index.html
  </code></pre>
  
  <p>Why this problem sudenlly  appeared? How to fix it? If you need any additional information's please let me know and i will provide.
  Thank you in advance</p>