# ScriptableObject not working after build in Unity?

I have a GameObject with a ScriptableObject on it, stats. It works fine in editor but when I try to build I get a message,

A script behaviour (script unknown or not yet loaded) has a different serialization layout when loading.

What is wrong here?

It turns out, I had changed the ScriptableObject (added a new property) after I'd already created the .asset file.
Going to the .asset file and re-setting the Script component fixed this. Making a new one would also work.