{"<user xmlns=''> was not expected.} Deserializing Twitter XML

Even easier is just to add the following annotations to the top of your class:

[Serializable, XmlRoot("user")]
public partial class User

XmlSerializer xs = new XmlSerializer(typeof(User), new XmlRootAttribute("yourRootName")); 

Either decorate your root entity with the XmlRoot attribute which will be used at compile time.

[XmlRoot(Namespace = "www.contoso.com", ElementName = "MyGroupName", DataType = "string", IsNullable=true)]

Or specify the root attribute when de serializing at runtime.

XmlRootAttribute xRoot = new XmlRootAttribute();
xRoot.ElementName = "user";
// xRoot.Namespace = "http://www.cpandl.com";
xRoot.IsNullable = true;

XmlSerializer xs = new XmlSerializer(typeof(User),xRoot);