Type Reason ArgumentException A string containing the text would result in a non-well formed XML document, or name is either null or string.Empty. InvalidOperationException The XmlTextWriter.WriteState is WriteState.Closed.
In the dnprdnext release, the recommended practice is to create System.Xml.XmlWriter instances using the erload:System.Xml.XmlWriter.Create method and the System.Xml.XmlWriterSettings class. This allows you to take full advantage of all the new features introduced in this release. For more information, see Creating XML Writers.