how do assign image to picturebox

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C#

picturebox

I'm using visual c# 2013 ultimate. My project has several image that i assigned to picture box and don't have any problem with this. But now, when i want to add new picturebox,i can't assign new image to it.Whereas it was not before. Design mode don't have a problem and image is properly assigned to picture box. But in running mode,new picturebox don't have any image and show empty picturebox , just show bgcolor. But other picturebox don't have any problem. What is wrong?
"in this code 300720131281 is a valid jpg"

this.pictureBox4.Image = global::bimeh_ok.Properties.Resources._300720131281;
    this.pictureBox4.Location = new System.Drawing.Point(36, 181);
    this.pictureBox4.Name = "pictureBox4";
    this.pictureBox4.Size = new System.Drawing.Size(100, 50);
    this.pictureBox4.SizeMode = System.Windows.Forms.PictureBoxSizeMode.StretchImage;
    this.pictureBox4.TabIndex = 302;
    this.pictureBox4.TabStop = false;

actually, image that build with the following code in 'resources.rex' is returned null ! why??

internal static System.Drawing.Bitmap _300720131281 {
           get {
               object obj = ResourceManager.GetObject("300720131281", resourceCulture);
               return ((System.Drawing.Bitmap)(obj));
           }
       }