Could not start a new session

[Ana MB]

Hi guys!

I have a problem with my Jenkins server. I'm trying to run different tests but I can't do it. I get the following error: 

main(paquete.ImagenMarca_GoogleAnualTest)  Time elapsed: 0.383 sec  <<< FAILURE!

org.openqa.selenium.remote.UnreachableBrowserException: Could not start a new session. Possible causes are invalid address of the remote server or browser start-up failure.

Build info: version: '3.4.0', revision: 'unknown', time: 'unknown'

System info: host: 'DS0', ip: '127.0.1.1', os.name: 'Linux', os.arch: 'amd64', os.version: '3.13.0-105-generic', java.version: '9'

Driver info: driver.version: RemoteWebDriver

	at org.openqa.selenium.remote.RemoteWebDriver.execute(RemoteWebDriver.java:658)

	at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:250)

	at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:236)

	at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:137)

	at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:174)

	at paquete.ImagenMarca_GoogleAnualTest.main(ImagenMarca_GoogleAnualTest.java:49)

Caused by: org.apache.http.conn.HttpHostConnectException: Connect to 163.999.104.101:4444 [/163.999.104.101] failed: Connection refused (Connection refused)

I don't know why it's happening because my server is up ready to use... I restarted it and nothing changed.... any ideas??

Thanks so much for your help!!!