Changing the Header name in Datagridview in C#.net

private void btnBrows_Click(object sender, EventArgs e)
        {
            DialogResult result = ofd.ShowDialog(); // Show the dialog.
            if (result == DialogResult.OK) // Test result.
            {
                string file = ofd.SafeFileName;
                string Extension = Path.GetExtension(ofd.FileName);
                Import_To_Grid(ofd.FileName, Extension, isRDB);

            }
        }

        private void Import_To_Grid(string FilePath, string Extension, string isHDR)
        {
            string conStr = "";
            switch (Extension)
            {
                case ".xls": //Excel 97-03
                    conStr = ConfigurationManager.ConnectionStrings["Excel03ConString"].ConnectionString;
                    break;
                case ".xlsx": //Excel 07
                    conStr = ConfigurationManager.ConnectionStrings["Excel07ConString"].ConnectionString;
                    break;
            }
            conStr = String.Format(conStr, FilePath, isHDR);
            OleDbConnection connExcel = new OleDbConnection(conStr);
            OleDbCommand cmdExcel = new OleDbCommand();
            OleDbDataAdapter oda = new OleDbDataAdapter();
            DataTable dt = new DataTable();
            cmdExcel.Connection = connExcel;

            //Get the name of First Sheet
            connExcel.Open();
            DataTable dtExcelSchema;
            dtExcelSchema = connExcel.GetOleDbSchemaTable(OleDbSchemaGuid.Tables, null);
            string SheetName = dtExcelSchema.Rows[0]["TABLE_NAME"].ToString();
            connExcel.Close();

            //Read Data from First Sheet
            connExcel.Open();
            cmdExcel.CommandText = "SELECT * From [" + SheetName + "]";
            oda.SelectCommand = cmdExcel;
            oda.Fill(dt);
            connExcel.Close();

            //Bind Data to GridView

            dataGridView1.DataSource = dt;

        }
        string isRDB = string.Empty;
        private void rdbY_CheckedChanged(object sender, EventArgs e)
        {
            isRDB = "Yes";
        }

        private void rdbN_CheckedChanged(object sender, EventArgs e)
        {
            isRDB = "No";
        }

<connectionstrings>
    <add name="Excel03ConString" connectionstring="Provider=Microsoft.Jet.OLEDB.4.0;Data Source={0}; Extended Properties='Excel 8.0;HDR={1}'" />
    <add name="Excel07ConString" connectionstring="Provider=Microsoft.ACE.OLEDB.12.0;Data Source={0}; Extended Properties='Excel 8.0;HDR={1}'" />
  </connectionstrings>