It may have something to do with the Java version you are using, a lot of people can't use 1.6 u2 on their comps, but some can, not sure as to why..
So try uninstalling all versions of Java from the add/remove programs and then re-install the JRE 5.11 offline version....
Archive: Download Java 2 Platform Standard Edition (J2SE) 5.0 Update 11