How to display xml string in a Label?

I am trying to get my HTML method below, to encode the string and display it on label, but I keep getting a blank page, on the client-side.

I have checked the viewsource and it shows no HTML output their also.

public partial class About : Page
  {
    protected void Page_Load(object sender, EventArgs e, string data)
    {
        if (!IsPostBack)
        {
            string a = createXMLPub(data);
            // Label1.Text = HttpUtility.HtmlEncode(a);
            Label1.Text = Server.HtmlEncode(a);
        }
    }

public static string createXMLPub(string data )
{
    XElement xeRoot = new XElement("pub");
    XElement xeName = new XElement("name", "###");
    xeRoot.Add(xeName);
    XElement xeCategory = new XElement("category", "#####");
    xeRoot.Add(xeCategory);
    XDocument xDoc = new XDocument(xeRoot);
    data = xDoc.ToString();
    return data;

}

HTML

 <asp:Content runat="server" ID="BodyContent" ContentPlaceHolderID="MainContent">
 <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>
 </asp:Content>

Please advice, to where I may be going wrong with this code. Many thanks