800A03EC Error excel chart export on second try

[flouger]

Hi when I try to export a chart programmability to an image i receive
the 800A03EC error on the second try. The first try works well
though. Im not really sure what to try next any thoughts?
Here is my code listing

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;

namespace DisplayEditor
{
public partial class ExcelChartSelector2 : Form
{
public string FileName;
public string ChartName;
Excel.Application ExcelObj;
Excel.Workbook workBook ;
protected override void OnClosing(CancelEventArgs e)
{
workBook.Close(false, System.Reflection.Missing.Value,
System.Reflection.Missing.Value);
base.OnClosing(e);
}
public ExcelChartSelector2()
{
InitializeComponent();
}

private void ExcelChartSelector2_Load(object sender, EventArgs
e)
{
ExcelObj = new Excel.Application();
//System.Globalization.CultureInfo enUS = new
System.Globalization.CultureInfo("en-US");
//System.Threading.Thread.CurrentThread.CurrentCulture =
enUS;
object missing = System.Reflection.Missing.Value;
workBook = ExcelObj.Workbooks.Open(FileName, missing,
missing, missing, missing, missing, missing, missing, missing,
missing, missing, missing, missing);
//Excel.Chart chart = workBook.Sheets;
foreach(Excel.Chart chart in workBook.Charts ){
listBox1.Items.Add(chart.Name);
}

//workBook.Close(false, System.Reflection.Missing.Value,
System.Reflection.Missing.Value);

//Excel.Chart chart =
((Excel.Worksheet)sheets[chartName]).ChartObjects(0);
//chart.Export(@".\temp\1.gif", "GIF", false);//save it
//load it to be displayed
//Image i = new Bitmap(@".\temp\1.gif");
}

private void listBox1_SelectedIndexChanged(object sender,
EventArgs e)
{

//workBook = ExcelObj.Workbooks.Open(FileName, false,
true, 5, "", "", true, Excel.XlPlatform.xlWindows, "", false, false,
0,false );
Excel.Chart chart = (Excel.Chart)
workBook.Charts[listBox1.SelectedItem];
ChartName = chart.Name;
try { System.IO.File.Delete(@".\temp\1.gif"); }
catch (Exception ee) { }

try
{

System.Threading.Thread.CurrentThread.CurrentCulture=
new System.Globalization.CultureInfo("en-US");
chart.Export(@".\temp\1.gif", "gif", false);//save it



}
catch (Exception ee)
{
MessageBox.Show(ee.Message);
}


//load it to be displayed
Image i = new Bitmap(@".\temp\1.gif");
pictureBox1.Image = i;
}
}
}