How to make my floor solid

I have been trying to make my floor a solid but it doesn't work my player keep falling throught the map I have contacted unity no response help me please.

 

How to report your problem productively in the Unity3D forums:

http://plbm.com/?p=220

This is the bare minimum of information to report:

- what you want
- what you tried (details about ALL the things you put into ensuring your floor is solid: eg, "I'm using a rigidbody, I have these colliders set, here is the code that is moving my player, here is the documentation why I think it is correct, etc.)
- what you expected to happen
- what actually happened, especially any errors you see
- links to documentation you used to cross-check your work (CRITICAL!!!)

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