exporting an file as fbx fails

I know this is a couple years old, but people may be experiencing this problem in the future. Here are couple of things you can try to avoid this error.

• This may happen if you smart UV unwrap an object. You may have to manually do the uv map or use a cube, cylinder and/or sphere projection.
• Double check the materials on objects, you may be experiencing a 'list index out of range'. This reddit post explains it well.
• Objects with invalid location and extremely high or low scales also can throw errors.
• If you aren't concerned about materials on the object, trying exporting as an obj, then reimport into blender and export once again as a fbx.

Hope this helps. It may be a bit of trial and error.

I know this is years ago, but I found a solution where one of my bones was scaled to 0. I reset the scale and it exported fine

I tried the option of exporting as a obj but lost the animations, I also renamed all my UVMaps and still it did not work. I had a lot of animations for my character and when i removed some of these it seemed to work ok, so if the other options fail, try that.

I had this problem, export as obj, reload start up file, import the obj then export as fbx.