Could not start a new session. Possible causes are invalid address of the remote server.......
Problem: This again was an issue that I found when I tried setting up the selenium test automation framework on a new machine.
Things that you need to check to solve this issue.
First thing check the version of JRE in your project, the javac compiler in your IDE.
Changing the JRE System Library from jdk1.7.0 to jre7
Make sure the classpath is set correctly pointing to the JRE and JDK
If you are using ANT make sure you have the ant libraries in the right place.
Also make sure you have the tools.jar under Ant - Runtime - global libraries.
That worked for me, hope it helps anyone facing the same issue.