Java Update Prompts Save Code Difficulties
Oracle added an update to Java that breaks the way that save codes work on VirtualNES.com. We've been working on a proper transition to the same system presently utilized by VirtualGBX.com and VirtualSuperNES.com. We're aware of the problem, and are in the process of developing a replacement.
This only affects games that have save codes handled by Java on this website, it doesn't affect games without save codes, such as Super Mario Bros. 3.