Importing a Skinned Mesh Breaks the Normals

I’m trying to import a skinned mesh from Maya 2018 to Unity 2018.2.6f1. I had previously been trying to import from Maya 2017 to a recent but earlier version of Unity and had the same issue, updating my software didn’t change anything. When I import a standard mesh, everything is fine. However, as soon as I bind the mesh to a skeleton, the normals get messed up.

In the picture, the mesh on the left is the unbound mesh with correct lighting. The mesh on the right is after I’ve bound it to a skeleton. I’ve been searching the forums for answers, but nothing has helped. Changing the import settings in Unity on the skinned mesh from import normals to calculate normals doesn’t change anything. Deleting the non-deformer history, unchecking “animations”, using Set-to-Face/Soften Edges/(Un)Lock Normals in Maya also doesn’t help.

I haven’t seen anything like this before, nor has anyone else I’ve asked. Any ideas?

How many bones do you have and to how many bones is a single vertex bound to at the same time? Unity only supports 4 bone weights per vertex. So every vertex can only be bound to 4 bones max. If the quality settings is actually set to a lower profile it might be only 2 or 1 bone.