Getting "" at the beginning of my XML File after save() [duplicate]

It is the UTF-8 BOM, which is actually discouraged by the Unicode standard:

http://www.unicode.org/versions/Unicode5.0.0/ch02.pdf

Use of a BOM is neither required nor recommended for UTF-8, but may be encountered in contexts where UTF-8 data is converted from other encoding forms that use a BOM or where the BOM is used as a UTF-8 signature

You may disable it using:

var sw = new IO.StreamWriter(path, new System.Text.UTF8Encoding(false));doc.Save(sw);sw.Close();

It's a UTF-8 Byte Order Mark (BOM) and is to be expected.

You can try to change the encoding of the XmlDocument. Below is the example copied from MSDN

using System; using System.IO; using System.Xml;public class Sample {  public static void Main() {    // Create and load the XML document.    XmlDocument doc = new XmlDocument();    string xmlString = "<book><title>Oberon's Legacy</title></book>";    doc.Load(new StringReader(xmlString));    // Create an XML declaration.     XmlDeclaration xmldecl;    xmldecl = doc.CreateXmlDeclaration("1.0",null,null);    xmldecl.Encoding="UTF-16";    xmldecl.Standalone="yes";         // Add the new node to the document.    XmlElement root = doc.DocumentElement;    doc.InsertBefore(xmldecl, root);    // Display the modified XML document     Console.WriteLine(doc.OuterXml);  } 

}