Step 1:

      Create the following class in APP_CODE folder

                 public class MyTest : IHttpHandler

{

      public bool IsReusable

    {

        get

        {

            return false;

        }

    }

    public void ProcessRequest(HttpContext ob)

    {

        ob.Response.Redirect("Default.aspx");

    }

}

                Step 2:

      Modify the web.config file to include below line:

                 < add verb = "*"path="*.xyz"type="MyTest" />

                It should be added under <system.web>  <httpHandlers>  tags like:

                < httpHandlers >

< add verb = "*"path="*.asmx"validate="false"type="System.Web.Extensions,

System.Web.Extensions, Version=3.5.0.0, 

                  Culture=neutral, PublicKeyToken=31B35 "/>

            < add verb = "*"path="*.xyz"type="MyTest" />

</ httpHandlers >