http://developers.de/blogs/rolf_nebhuth/archive/2009/05/13/signing-xml-documents.aspxIf you want to check if an XML is not changed, you can sign an XML file. Following Code show you how to sign a XML document. X509Certificate2 cert = loadCertifate(); XmlDocument doc = new XmlDocument (); doc.PreserveWhitespace = true ; doc.Load( @"cenCommunityServer 2008 SP1 (Build: 30619.63)