Unity Importing Model Error

I have a problem when exporting a model from blender to unity.
Sometimes the mesh is semi-transparent.

In Blender as you can see on the image the model is perfect, but when opened in unity it is semi-transparent.

In Unity it is using Diffuse shader (But whatever the shader continues in the same way)

ERROR SS:
https://www.dropbox.com/s/jxje3agwq4k6wsv/unity error.png


*****************EDIT
Sorry for the post ... I found the solution in the forum.
http://forum.unity3d.com/threads/15148-mesh-transparent