If you are getting a Failed to validate certficate. the application wll not be executed error then its related to java security.
To fix this:

1. Go to the java icon (in the task bar) , right click , choose "Open Control Panel"
2. Under the "Advanced" tab you go under Security node , expand it and uncheck "Enable list of trusted publishers"
3. Next time you open the application it will ask you if you trust the source , you click yes and then go ..


To see if your Java is installed correctly try out this applet at http://www.schubart.net/rc/.
If this fails then possibly reinstall Java with the latest version.