Error in C# winform while show a new form

Question

Hi all,

am developing a C# Winform Application.Am using the MDI form in my application also i placed a Tab Control in MDI main form.When i tried to show a new form as a MDIchild,But it not showing .

  private void mnuForm1_Click(object sender, EventArgs e)
{
Form1 frm1= new Form1();
frm1.MdiParent = this;
frm1.Show();
}

 

am getting the

"A first chance exception of type 'System.ArgumentException' occurred in mscorlib.dll " Error in output window.If i delete that Tab control form MDI then its working...

Here,

  What's wrong with adding TabControl in MDIform.

 

Thanks in Advance..