Types and namespace not found...

Ok, so I'm new to Unity and C# but I wrote a tiny script which runs without a problem inside Unity. But when I try to export it (build) I get a bunch of errors all telling me types are not found, and it's pretty much all the types I used... So it doesn't find MonoBehaviour, Vector3 or Transform.

The script looks like this :

• using System.Collections.Generic; using UnityEngine; public class CameraBehaviour : MonoBehaviour { Vector3 myVectorZ; Vector3 myVectorY; Vector3 myVectorX; Transform myTransform; void Awake () {

      myTransform = GetComponent<Transform> ();
           
       myVectorZ = new Vector3 (myTransform.position.x, myTransform.position.y, myTransform.position.z+2);
       myVectorY = new Vector3 (myTransform.position.x, myTransform.position.y+2, myTransform.position.z);
       myVectorX = new Vector3 (myTransform.position.x+2, myTransform.position.y, myTransform.position.z);
   }
   // Use this for initialization
   void Start () {
       
   }
   
   // Update is called once per frame
   void FixedUpdate () {
       if ( Input.GetKey( "space" ) )
       { transform.Translate( myVectorZ , Space.Self);
           Debug.Log ("Fixed :");
           Debug.Log (myTransform.position.z); }
   }
   void Update () {
       if ( Input.GetKey( "space" ) )
       { transform.Translate( myVectorZ , Space.Self);
           Debug.Log ("NotFixed :");
           Debug.Log (myTransform.position.z); }
   }
  

} *

I'm guessing I didn't think of a simple thing that ruin everything but I didn't find an answer fitting my problem. Sorry if I'm not clear, not english... Thanks in advance for your answers !