private void RemoveLibrary(int rowStart, Excel.Worksheet xlWorkSheet)
        {
            this.richTextBox1.AppendText("Deleting .....\n");
            List <string> Lst = spManager.GetLists(out result);

            /// if any result happens during retriving the data
            this.richTextBox1.AppendText(result);
            for (int iRow = rowStart; iRow <= xlWorkSheet.Rows.Count; iRow++)
            {
                if (xlWorkSheet.Cells[iRow, 1].value == null)
                {
                    break;      // BREAK LOOP.
                }
                else
                {
                    string lib = (string)xlWorkSheet.Cells[iRow, 1].value;
                    lib    = Regex.Replace(lib, @"\s+", "").Trim();
                    result = spManager.DeleteList(lib);
                    this.richTextBox1.AppendText(result);
                }
            }
        }