public static void Main()
string input = @"<Servers> <MyNewServer> <Host>10.10.10.2</Host> <Port>12</Port> <User>MyUser</User> <Password>NkbgKnF9g96EYgxG3qRdCNY2KR6Xd5+0uqpY9KOCl4k=</Password> </MyNewServer></Servers>";
var doc = XDocument.Parse(input);
doc.Descendants("Servers").First()
.Add( new XElement("OneMoreServer", new [] {