   at a1r.b6(String A_0)   at CSI.ETABS.mdiMainForm.DisposeAllMDIForms()
   at CSI.ETABS.mdiMainForm.mdiMainForm_FormClosing(Object sender, FormClosingEventArgs e)
   at System.Windows.Forms.Form.OnFormClosing(FormClosingEventArgs e)
   at System.Windows.Forms.Form.WmClose(Message& m)
   at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)