/// <summary>
        /// Handle manifest open command
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void OnFileOpen(object sender, EventArgs e)
        {
            // Prompt for location of deployment manifest
            OpenFileDialog ofd = new OpenFileDialog();

            ofd.Filter = "Deployment Manifests (*.application)|*.application|All Files(*.*)|*.*";

            // Restore last manifest location if available
            if (!string.IsNullOrEmpty(Settings.Default.LastManifestPath) &&
                Directory.Exists(Settings.Default.LastManifestPath))
            {
                ofd.InitialDirectory = Settings.Default.LastManifestPath;
            }

            // Path selected
            if (ofd.ShowDialog() == DialogResult.OK)
            {
                string fileName = ofd.FileName;

                // Save for next time
                Settings.Default.LastManifestPath = Path.GetDirectoryName(fileName);
                Settings.Default.Save();
                bool appManifestAvail = false;

                // Load the details
                try
                {
                    ManifestHelper.LoadDeploymentManifestData(fileName, out m_DeployManifest, out m_AppManifest);
                    appManifestAvail = true;
                }
                catch (FileNotFoundException fex)
                {
                    MessageBox.Show("Unable to locate referenced application manifest\n" + fex.FileName);
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message);
                    return;
                }

                // Update UI fields
                appIdTextBox.Text       = m_DeployManifest.AssemblyIdentity.Name;
                versionTextBox.Text     = m_DeployManifest.AssemblyIdentity.Version;
                depProviderTextBox.Text = m_DeployManifest.DeploymentUrl;

                // Update app manifest details
                if (appManifestAvail)
                {
                    m_Prerequisites = ManifestHelper.GetPrerequisites(m_AppManifest);
                    m_Files         = ManifestHelper.GetFiles(m_AppManifest);
                    filesBindingSource.DataSource = m_Files;
                    //If the user used mage at all, it will replace the space in "Application Files" with a %20.
                    //Check for it and replace it if found. RobinDotNet 4/7/2010
                    appManifestPathTextBox.Text = m_DeployManifest.EntryPoint.TargetPath.Replace("%20", " ");
                    EnableToolStripItems(true);
                }
                else
                {
                    EnableToolStripItems(false);
                }
                _dirty = false;
            }
        }