ok so in JMonkey i try to open a new empty jme3 scene. and i get this error.
error opening newScene.j3o.
any help?
What does your scene have? Look at the output error, by clicking at the small red sphere on the bottom right, and post it here so we can check it. Also, maybe updating the SDK can solve the problem : https://wiki.jmonkeyengine.org/legacy/doku.php/sdk:update_center.