Hey. I’ve got a .fbx imported to a demo scene. The demo scene contains a model that animates fine.
I drag my .fbx to the hierarchy and then back to my folder again to make a prefab, after going into “Rig” and making sure the muscles move the bones.
However when I click an animation and drag my prefab into the preview window, it won’t animate! The demo prefabs animate just fine 
The unity model doesn’t work either when I try to make that the preview model!
@bjarnidk You don’t mention what type of animations you use? Legacy or Mecanim? That makes a difference. You stated that you went into the Rig and made sure the muscles move the bones?
Did you check that your new character is the same setup as your demo character that does work?
If the demo character is marked humanoid, then your replacement character must also be Humanoid or it wont work. Could you please be more specific as to what type of animation system you are using.
Check both Rigs, in the drop down under rig, beside animation type, check that both are using the same type. if your new model is different from your demo one, choose the demo type and hit apply.
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