this works fine for me...

Code:
        private void textBox1_KeyUp(object sender, KeyEventArgs e)
        {
            if (e.KeyCode == Keys.Enter)
            {
                Label label = new Label();
                label.Name = "label" + textBox1.Text;
                label.Location = new Point(10,10);
                label.Size = new Size(30, 30);
                label.Text = textBox1.Text;
                panel1.Controls.Add(label);
            }
        }