Selenium: Invalid “already running” error when starting server

Question

I am trying to get the Selenium server up and running. However, when I type:

java -jar selenium-server-standalone-2.0b3.jar

I get an Exception

Answer 1

I had the same error but no server was running. Tuned out the java version was in cause. Make sure you are running java 7 or higher:

java -version