BindSkin:cannot find transform 'FLOOR'

When I press the play button, I find that my character clipper/fall through the floor mesh as if it was not there.

in the error console/window it came up:

[mecanism]: Bind Skeleton: Cannot find Transform 'FLOOR' (this error comes up for every frame as my character falls through.

What I have done was I applied box collision for the floor, with isTrigger checked.

For my character model, i had: -apply Rigidbody and checked is Kinematic, interpolate none, Collision Detection Discrete, rest is on default.

At the moment i am using the latest unity free version.