C# と VB.NET の質問掲示板

タイマーで一定時間毎にpanelのサイズを変更するようにします。
panelにはpictureboxをドッキングしています。
タイマーをまわすとエラーが出ます。
どのようにしたらいいかいき詰まってます。
よろしくお願い致します。

namespace timer
{
    public partial class Form1 : Form
    {

        private System.Timers.Timer m_t = null;
        private System.Windows.Forms.Panel panel2;
        private System.Windows.Forms.PictureBox pictureBox2;

        public Form1()
        {
            InitializeComponent();
            InitializeSet();
            TimerInitialize();
        }

        private void InitializeSet()
        {
            this.panel2 = new System.Windows.Forms.Panel();
            this.pictureBox2 = new System.Windows.Forms.PictureBox();
            this.panel2.SuspendLayout();
            ((System.ComponentModel.ISupportInitialize)(this.pictureBox2)).BeginInit();
            this.SuspendLayout();
   
            this.panel2.AutoSize = true;
            this.panel2.Controls.Add(this.pictureBox2);
            this.panel2.Location = new System.Drawing.Point(0, 0);
            this.panel2.Name = "panel2";
            this.panel2.Size = new System.Drawing.Size(150, 118);
            this.panel2.BackColor = Color.Red;
            this.panel2.TabIndex = 6;
            this.panel2.TabStop = true;
            this.panel2.UseWaitCursor = true;

            this.pictureBox2.Dock = System.Windows.Forms.DockStyle.Left;
            this.pictureBox2.Location = new System.Drawing.Point(10, 10);
            this.pictureBox2.Name = "pictureBox2";
            this.pictureBox2.Size = new System.Drawing.Size(100, 118);
            this.pictureBox2.BackColor = Color.Blue;
            this.pictureBox2.TabIndex = 7;
            this.pictureBox2.TabStop = false;
            this.pictureBox2.UseWaitCursor = true;

            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 12F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(284, 262);
            this.Controls.Add(this.panel2);
            this.Name = "Form1";
            this.Text = "Form1";
            this.panel2.ResumeLayout(false);
            ((System.ComponentModel.ISupportInitialize)(this.pictureBox2)).EndInit();
            this.ResumeLayout(false);
            this.PerformLayout();
        }

        private void TimerInitialize()
        {
            this.m_t = new System.Timers.Timer();
            this.m_t.Enabled = true;
            this.m_t.Interval = 1000;
            this.m_t.Elapsed += M_t_Elapsed;

        }

        private void M_t_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
        {
            try
            {
                this.panel2.Size = new Size(100, 100);
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.ToString());

            }
        }
    }
}