не срабатывает Picturebox_DragEnter

вроде все правильно написал, но Drag enter не работает. allowdrop где находится я не нашел что можно сделать?

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;
namespace _8
{
    public partial class Form3 : Form
    {
        public Form3()
        {
            InitializeComponent();

        }
        private void pictureBox5_MouseDown(object sender, MouseEventArgs e)
        {
             pictureBox5.DoDragDrop(pictureBox5.Image, DragDropEffects.Copy | DragDropEffects.Move);
        }
        private void pictureBox6_MouseDown(object sender, MouseEventArgs e)
        {
            pictureBox6.DoDragDrop(pictureBox6.Image, DragDropEffects.Copy | DragDropEffects.Move);
         }

        private void pictureBox7_MouseDown(object sender, MouseEventArgs e)
        {
            pictureBox7.DoDragDrop(pictureBox7.Image, DragDropEffects.Copy | DragDropEffects.Move);
        }
        private void pictureBox8_MouseDown(object sender, MouseEventArgs e)
        {
            pictureBox8.DoDragDrop(pictureBox8.Image, DragDropEffects.Copy | DragDropEffects.Move);
        }


        private void pictureBox1_DragEnter(object sender, DragEventArgs e)
        {
            label1.Text = "1122";
           // if (e.Data.GetDataPresent(DataFormats.Bitmap) || e.Data.GetDataPresent(DataFormats.Text))
            e.Effect =DragDropEffects.Copy;

        }
        private void pictureBox1_DragDrop(object sender, DragEventArgs e)
        {
            List<string> dek = new List<string>();
            string deks = (string)e.Data.GetData(DataFormats.Text);
            label1.Text = "111";
            var bmp = (Bitmap)e.Data.GetData(DataFormats.Bitmap);
            pictureBox1.Image = bmp;
        }
    }
}