C# NullReferenceException: Object reference not set to an instance of an object

Hey.
I need some help with my NetworkManager Script. The Error is:

NullReferenceException: Object reference not set to an instance of an object
NetworkManagerStarting.SpawnMyPlayer () (at Assets/OwnScripts/NetworkManagerStarting.cs:56)
NetworkManagerStarting.OnJoinedRoom () (at Assets/OwnScripts/NetworkManagerStarting.cs:49)
UnityEngine.GameObject:SendMessage(String, Object, SendMessageOptions)
NetworkingPeer:SendMonoMessage(PhotonNetworkingMessage, Object[]) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs:1769)
NetworkingPeer:OnEvent(EventData) (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/NetworkingPeer.cs:1612)
ExitGames.Client.Photon.PeerBase:DeserializeMessageAndCallback(Byte[])
ExitGames.Client.Photon.EnetPeer:DispatchIncomingCommands()
ExitGames.Client.Photon.PhotonPeer:DispatchIncomingCommands()
PhotonHandler:Update() (at Assets/Photon Unity Networking/Plugins/PhotonNetwork/PhotonHandler.cs:76)

using UnityEngine;
using System.Collections;

public class NetworkManagerStarting : MonoBehaviour {
	
	public Camera standbyCamera;
	
	GameObject mySpawnSpot;
	GameObject myPlayerGO;
	
	public bool offlineMode = false;
	
	// Use this for initialization
	void Start () {
		Connect ();
		
	}
	
	void Update () {
		
	}
	
	void Connect ()  {
		if (offlineMode) {
			PhotonNetwork.offlineMode = true;
			OnJoinedLobby();
		} else {
			PhotonNetwork.ConnectUsingSettings ("TestVersion0.0.1");
		}
	}
	
	void OnGUI(){
		GUILayout.Label (PhotonNetwork.connectionStateDetailed.ToString ());
	}
	
	
	void OnJoinedLobby() {
		PhotonNetwork.JoinRandomRoom();
	}
	
	void OnPhotonRandomJoinFailed () {
		PhotonNetwork.CreateRoom( null );
	}
	
	void OnJoinedRoom(){
		Debug.Log ("JoinedRoom");
		
		SpawnMyPlayer();
	}
	
	void SpawnMyPlayer() {
		
		mySpawnSpot = GameObject.FindWithTag("Spawnspot");
		Debug.Log ("Spawnspot   check");
		myPlayerGO = (PhotonNetwork.Instantiate ("PlayerController", mySpawnSpot.transform.position, mySpawnSpot.transform.rotation,0));
		if(myPlayerGO != null) {Debug.LogError("WTF?!?!?!?!"); return; }
		standbyCamera.enabled = false;
		Debug.Log ("fpsready");
		((MonoBehaviour)myPlayerGO.GetComponent ("MouseLook")).enabled = true;
		Debug.Log ("msready");
		((MonoBehaviour)myPlayerGO.GetComponent ("FPSInputController")).enabled = true;
		Debug.Log ("psready");
		myPlayerGO.transform.FindChild ("MainCamera").gameObject.SetActive (true);
		Debug.Log ("camready");
		((MonoBehaviour)myPlayerGO.GetComponent ("CharacterMotor")).enabled = true;
		Debug.Log ("charready");
		Debug.Log ("playready");
		
	}
}

Object reference not set to an instance of an object

This error could mean you tried using the property of an object that doesn’t exist.

Make sure all the objects in your SpawnMyPlayer() exist by logging them.

Eg:
Debug.Log(standbyCamera);
Debug.Log(myPlayerGO);
Debug.Log(mySpawnSpot);

You might find that something in there is null.