Unity 5 - Can't move/control object

Hello,

If I open a project from Unity 4.6 in Unity 5 I can't control my object anymore. I also created new project in Unity 5, set a scene with some ground and object (cube) that I want to move with my keyboard keys. I attach script to object and start the scene but object is not moving. Same thing is working in Unity 4.6.

Script is very simple:

 using UnityEngine;
 using System.Collections;
         
         public class Move : MonoBehaviour {
         
             public int speed = 0;
             private Vector3 input;
      
             void FixedUpdate(){
                 Vector3 input = new Vector3(Input.GetAxis ("Horizontal"), 0, Input.GetAxis("Vertical"));
                 GetComponent<Rigidbody>().AddForce(input * speed * Time.deltaTime);
             }
         }

I'm not using any kind of animations in my project.

EDIT

I opened my Unity 4.6 and project that I'm working on (project was not opened with Unity 5), and now even there I can't move my object. Maybe some conflict betwen Unity 4.6 and Unity 5?

EDIT2

I unistalled Unity 5 and now I can't make object to move even in Unity 4.6. Like it is glued to ground, I can see some force added to object (it shakes a little on top).