While I am trying to open Apex Editor it gives the error message 'Unable to launch application' and is not opening. Kindly help.
I've checked various discussion forums and boards and users reported this issue as well. The problem resides within your Java installation. I recommend you reinstall all the Java packages you have in your PC and then try launching the Apex Editor one more time. If I am right, it should work out of the box without any other tweaking or customization needed.
For all the Java Downloads, use the following link: http://www.oracle.com/technetwork/java/index.html