anyone have experience on manipulating XML document with ASP.NET?

I'm trying to load a xml file then append a child then save it. This is similiar to what I have..


reader = new XmlTextReader (Server.MapPath("abc.xml"))
reader.WhitespaceHandling = WhitespaceHandling.None
reader.MoveToContent()
reader.Read()

xmlDoc.Load(reader)

reader.Close

Dim root As XmlNode = xmlDoc.DocumentElement

Dim elem As XmlElement = xmlDoc.CreateElement("abc")

Dim fr As XmlAttribute = xmlDoc.CreateAttribute("from")
fr.Value = "whatever"


elem.SetAttributeNode(fr)

root.AppendChild(elem)

xmlDoc.Save(Server.MapPath("abc.xml"))


what must I do differently to make this work..?

Thank you.