Hiding and Storing/caching of Application Specific data in MS Word 2003 documents

using System;
using System.Collections.Generic;
using System.Windows.Forms;

namespace DocumentIDReader
{
    static class Program
    {
        public const int STRINGDATA_DOCUMENTID = 100;
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);
            Application.Run(new Form1());
        }
        public static void DisplayDocumentID(string documentName)
        {
            bool documentIDExists = false;
            FileOperation fileOperation=new FileOperation();
            string DocumentID=String.Empty;
            documentIDExists = fileOperation.ReadData(documentName, STRINGDATA_DOCUMENTID, ref DocumentID, 256);
            if (documentIDExists)
            {
               // MessageBox.Show("DocumentID Found ! \n ____________________________________________\n\n" + "ID : " + DocumentID, "Found", MessageBoxButtons.OK, MessageBoxIcon.Information);
                MessageBox.Show(DocumentID);
            }
            else
            {
              //  MessageBox.Show("DocumentID Not Found !! " + DocumentID, "Not Found", MessageBoxButtons.OK, MessageBoxIcon.Error);
                MessageBox.Show("DocumentID not found");

            }
        }

        public static void AddDocumentID(string documentName)
        {
            Boolean success = false;
            FileOperation fileOperation = new FileOperation();
            string DocumentID = Guid.NewGuid().ToString();

            success = fileOperation.AddData(documentName, STRINGDATA_DOCUMENTID, DocumentID);
            if (success==true)
                MessageBox.Show("DocumentID added ");
            //MessageBox.Show("DocumentID added ! \n ____________________________________________\n\n" + "ID : " +DocumentID,"success",MessageBoxButtons.OK,MessageBoxIcon.Information);
            else
                MessageBox.Show("Failed");
                //MessageBox.Show("Failed", "Failed", MessageBoxButtons.OK, MessageBoxIcon.Error);

        }
    }
}