Is the collider a trigger?
A trigger doesn't collide with rigid bodies. Instead it sends OnTriggerEnter, OnTriggerExit and OnTriggerStay message when a rigidbody enters or exits the trigger.
// Turns the attached to collider into a trigger.
collider.isTrigger = true;
using UnityEngine;
using System.Collections;
public class example : MonoBehaviour {
void Example() {
collider.isTrigger = true;
}
}
import UnityEngine
import System.Collections
class example(MonoBehaviour):
def Example():
collider.isTrigger = true