NavMesh baking finished very quickly and does not include some objects
<p>I am doing one of Unity's official tutorials: Survival Shooter.</p>

<p>Unity version: 5.3.4f1 Device: Macbook, OSX 10.11</p>

<p><a href="http://unity3d.com/learn/tutorials/projects/survival-shooter/environment?playlist=17144" rel="nofollow noreferrer">http://unity3d.com/learn/tutorials/projects/survival-shooter/environment?playlist=17144</a></p>

<p>The problem: Baking process completes almost instantly and the floor is not highlighted by a blue mesh (where highlight should mean that navmesh is calculated for there).</p>

<p>Here is the screenshot of it:
<a href="https://i.stack.imgur.com/xe9if.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xe9if.png" alt="enter image description here"></a></p>

<p>Then, I checked the completed scene (which was already created by Unity Team), it showed the floor fully highlighted. I just hit the bake again without touching anything and the same problem happened. So, there must be something else as I tried the original scene file without changing anything.</p>

<p>What am I missing here? Is there a Unity editor setting or something like that which can break the baking process?</p>