Converting to Legacy Animation Type breaks Animation

I have a model that is “Mecanim Ready”, 1 FBX file with the model, and another FBX file with an animation. The animations work fine and I can see the model animated in the preview window.

However, I need these to be Legacy animations for my project. Once I’ve converted the Animation Type to Legacy, I can no longer get the animation to work in game, or in the preview window.

How can I make legacy animations work? Problem explained on Youtube:

http://youtu.be/LrSBXddtexk

I found this error in the console:
“Imported animation (‘skeleton_mage@walk.fbx’) doesn’t match because there is a different amount of root nodes in the model file. Please unify the model and animation file, otherwise you won’t be able to play animation on the model.”

The structure of the model and the animation were different, coming from the artist.

To fix the problem, I opened the model and each animation with UU3D (http://www.unwrap3d.com/), and then I saved each file as a new FBX file.

I’m not sure which program the artist used, but simply saving these files with UU3D was enough to correct the node structure.