FileStream inFile = new FileStream(Server.MapPath("../../Temp/16.jpg"), System.IO.FileMode.Open, System.IO.FileAccess.Read);
byte[] binaryData = new Byte[inFile.Length];
long bytesRead = inFile.Read(binaryData, 0, (int)inFile.Length);
inFile.Close();
string base64String = "file1="+Convert.ToBase64String(binaryData, 0, binaryData.Length);
string strUrl = "http://11.11.11.111/Prova/recuperFile.aspx";
XMLHTTP objXMLhttp = new XMLHTTP();
objXMLhttp.open("POST", strUrl, false, "", "");
objXMLhttp.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
objXMLhttp.send(base64String);
if (objXMLhttp.status == 200) 
{
   msgErrore.Value=objXMLhttp.responseText;
}else{
    msgErrore.Value=objXMLhttp.responseText;
}