How to solve the problem with null and transform?[SOLVED]

Good morning everyone.

I wrote a script.

I use it for 2-3 days.

Everything was ok and worked great.

However,today, when I launched Unity, the following errors appear to me:

NullReferenceException: Object reference not set to an instance of an objectPathFollower1.Update () (at Assets/PathFollower1.cs:26)

UnityException: Transform child out of bounds PathFollower1.Start () (at Assets/PathFollower1.cs:20)

Does anyone know what is wrong? Why I have mistakes and how to solve it?

My script:

Code (CSharp):

1.  using System.Collections;
2.    using System.Collections.Generic;
3.    using UnityEngine;
4.  
5.    public class PathFollower1 : MonoBehaviour {
6.  
7.  
8.      public float speed = 3f;
9.      public Transform pathParent;
10.      Transform targetPoint;
11.  
12.      int index;
13.      public float speedRotate = 7f;
14.      Vector3 distance;
15.  
16.      Quaternion newRotate;
17.  
18.      // Use this for initialization
19.      void Start () {
20.          index = 0;
21.          targetPoint = pathParent.GetChild (index);
22.      }
23.      // Update is called once per frame
24.      void Update () {
25.          transform.position = Vector3.MoveTowards (transform.position, targetPoint.position, speed * Time.deltaTime);
26.          rotate ();
27.          if (Vector3.Distance (transform.position, targetPoint.position) < 0.1f)
28.          {
29.              index++;
30.              index %= pathParent.childCount;
31.              targetPoint = pathParent.GetChild (index);
32.          }
33.      }
34.      void rotate ()
35.      {
36.          distance = transform.position - targetPoint.position;
37.          newRotate = Quaternion.LookRotation (distance, transform.forward);
38.          newRotate.x = 0;
39.          newRotate.y = 0;
40.          transform.rotation = Quaternion.Lerp (transform.rotation, newRotate, speedRotate * Time.deltaTime);
41.      }
42. }

 

Maybe you didn't save you scene when you have quitted Unity.

public Transform pathParent is probably not set ( drag'n'drop ) in the Editor anymore

 

I save and also added in the inspector.
PS: In an object that after pressing play becomes a parent object, I have such a script:

Code (CSharp):

1.  using System.Collections;
2. using System.Collections.Generic;
3. using UnityEngine;
4.  
5. public class PathPlacer : MonoBehaviour {
6.  
7.      public float spacing = .1f;
8.      public float resolution = 1;
9.      public GameObject someObject;
10.  
11.      void Start () {
12.          Vector2[] points = FindObjectOfType<PathCreator>().path.CalculateEvenlySpacedPoints(spacing, resolution);
13.  
14.          foreach (Vector2 p in points)
15.  
16.          {
17.              GameObject g = GameObject.CreatePrimitive(PrimitiveType.Sphere);
18.              g.transform.parent = someObject.transform;
19.              g.transform.position = p;
20.              g.transform.localScale = Vector3.one * spacing * .5f;
21.          }
22.      }
23. }

 

Ok, I restarted and it works again ...