You can go ahead and install the JAVA update from the Apple by going to link below:
Once that is downloaded please go ahead and put the FXGfileformat.aip & launch illustrator and it should work for you.
If that doesnt work try to reset the prefrences for Illustrator.
Press and hold Option+Command+Shift (Mac OS) as you start Illustrator. Your current settings are deleted.
Let me know if you need further help on this.