Importing 3d objects - animated

While importing an animated 3D object into Unity, the characters normal is inverted. I have exported him without any animations and he exports fine. However, with animations it doe not work

I believe you might have a SCALE problem rather than a normals one.
Especially if you’re using BLENDER.

To fix:

1- start blender and in object mode select the mesh
2- press CTRL A and APPLY SCALE, this way the mesh scale will get re-set to 1 (negative parameters cause some pretty weird normals issues
2a- toggle on texture mode and look around your model to assure there's no gaping faces, in which case tab into edit mode, select all faces and press recalculate normals in the modify menu
3- export in fbx and drag into unity
4- in unity's inspector access the model and set its scale to 1 (it's 0.01 originally)